title: Exception after adding ProGuard to project
body: <p>I've added ProGuard to my project and got this error. I guess It can be Jsoup lib which I using to send POST and GET requests and parse responses. </p>
  
  <p>There are no separate line that throwns this exception.</p>
  
  <p>Can you help me to solve this problem with ProGuard?</p>
  
  <pre><code>java.lang.RuntimeException: An error occured while executing doInBackground()
          at android.os.AsyncTask$3.done(AsyncTask.java:299)
          at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
          at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
          at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
          at java.util.concurrent.FutureTask.run(FutureTask.java:137)
          at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
          at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
          at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
          at java.lang.Thread.run(Thread.java:864)
          Caused by: java.lang.ExceptionInInitializerError
          at org.jsoup.nodes.Document$OutputSettings.&lt;init&gt;(Unknown Source)
          at org.jsoup.nodes.Document.&lt;init&gt;(Unknown Source)
          at org.jsoup.parser.TreeBuilder.void initialiseParse(java.lang.String,java.lang.String,org.jsoup.parser.ParseErrorList)(Unknown Source)
          at org.jsoup.parser.TreeBuilder.org.jsoup.nodes.Document parse(java.lang.String,java.lang.String,org.jsoup.parser.ParseErrorList)(Unknown Source)
                                          boolean process(org.jsoup.parser.Token)
          at org.jsoup.parser.HtmlTreeBuilder.org.jsoup.nodes.Document parse(java.lang.String,java.lang.String,org.jsoup.parser.ParseErrorList)(Unknown Source)
                                              boolean process(org.jsoup.parser.Token)
                                              boolean process(org.jsoup.parser.Token,org.jsoup.parser.HtmlTreeBuilderState)
                                              void transition(org.jsoup.parser.HtmlTreeBuilderState)
                                              org.jsoup.parser.HtmlTreeBuilderState state()
                                              void framesetOk(boolean)
                                              void maybeSetBaseUri(org.jsoup.nodes.Element)
                                              org.jsoup.nodes.Element insert(org.jsoup.parser.Token$StartTag)
                                              org.jsoup.nodes.Element insert(java.lang.String)
                                              void insert(org.jsoup.parser.Token$Comment)
                                              void insert(org.jsoup.parser.Token$Character)
                                              boolean isElementInQueue(org.jsoup.helper.DescendableLinkedList,org.jsoup.nodes.Element)
                                              void popStackToClose(java.lang.String[])
                                              void insertOnStackAfter(org.jsoup.nodes.Element,org.jsoup.nodes.Element)
                                              void replaceInQueue(java.util.LinkedList,org.jsoup.nodes.Element,org.jsoup.nodes.Element)
                                              boolean inSpecificScope(java.lang.String,java.lang.String[],java.lang.String[])
                                              boolean inSpecificScope(java.lang.String[],java.lang.String[],java.lang.String[])
                                              boolean inScope(java.lang.String,java.lang.String[])
                                              void insertInFosterParent(org.jsoup.nodes.Node)
          at org.jsoup.parser.Parser.org.jsoup.nodes.Document parseInput(java.lang.String,java.lang.String)(Unknown Source)
                                     boolean isTrackErrors()
          at org.jsoup.helper.DataUtil.org.jsoup.nodes.Document parseByteData(java.nio.ByteBuffer,java.lang.String,java.lang.String,org.jsoup.parser.Parser)(Unknown Source)
                                       java.nio.ByteBuffer readToByteBuffer(java.io.InputStream,int)
                                       java.lang.String getCharsetFromContentType(java.lang.String)
          at org.jsoup.helper.HttpConnection$Response.org.jsoup.nodes.Document parse()(Unknown Source)
          at com.ThreeBoots.api.API.java.lang.Object userLogin(java.lang.String,java.lang.String)(Unknown Source)
                                    java.lang.Object userLoginFacebook(java.lang.String)
                                    boolean userLogout()
                                    boolean saveArticle(com.ThreeBoots.database.Article)
                                    java.lang.String loadPhoto(android.graphics.Bitmap)
                                    java.lang.String loadPhoto(android.widget.ImageView)
                                    java.lang.Object userSaveProfile(java.lang.String,java.lang.String,java.lang.String)
                                    java.lang.String sendRequest(java.lang.String,java.lang.String[])
                                    java.lang.String sendImageLoadRequest(java.lang.String,android.graphics.Bitmap)
                                    void processingBrands(org.json.JSONObject)
                                    java.lang.Object getListFromJSON(java.lang.Class,org.json.JSONArray)
                                    void insert(java.lang.Class,java.lang.Object)
          at com.ThreeBoots.api.API.java.lang.Object userRegister(java.lang.String,java.lang.String)(Unknown Source)
                                    boolean sync()
                                    java.lang.String sendRequest(java.lang.String)
                                    void processingMaterials(org.json.JSONObject)
          at com.ThreeBoots.api.API.java.lang.Object userRegister(java.lang.String,java.lang.String)(Unknown Source)
                                    boolean sync()
                                    java.lang.String sendRequest(java.lang.String)
                                    void processingMaterials(org.json.JSONObject)
          at com.ThreeBoots.asyncs.RequestAsync.java.lang.Object doInBackground(java.lang.String[])(Unknown Source)
                                                void asyncSaveArticlePostExecute(java.lang.Boolean)
                                                void asyncRegistrationPostExecute(java.lang.Object)
                                                void startMainActivity()
                                                void startLoginActivity(android.app.Activity)
          at com.ThreeBoots.asyncs.RequestAsync.java.lang.Object doInBackground(java.lang.Object[])(Unknown Source)
          at android.os.AsyncTask$2.call(AsyncTask.java:287)
          at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
          ... 5 more
          Caused by: java.lang.ExceptionInInitializerError
          at org.jsoup.nodes.Entities$EscapeMode.&lt;clinit&gt;(Unknown Source)
          ... 20 more
          Caused by: java.lang.NullPointerException
          at java.util.Properties.load(Properties.java:246)
          at org.jsoup.nodes.Entities.java.util.Map loadEntities(java.lang.String)(Unknown Source)
          at org.jsoup.nodes.Entities.&lt;clinit&gt;(Unknown Source)
          ... 21 more
  </code></pre>