title: maven-javadoc-plugin latest version issue
body: <p>I am using maven-javadoc-plugin 3.0.1(latest version). When I try to generate site information (project reports and etc), the javadoc does not show links to the dependent classes. All I see is full class name and no linkage. When I use maven-javadoc-plugin 2.10.4, everything works fine.</p>
  
  <p>Using maven 3.2.5 and java 8.</p>
  
  <p>Ran "mvn clean site -P profileID -X" for both versions of maven-javadoc-plugin and noticed below in the output:</p>
  
  <ol>
  <li>Case 3.0.1</li>
  </ol>
  
  <p>[</p>
  
  <pre><code>[INFO] Generating "Javadoc" report              maven-javadoc-plugin:3.0.1:javadoc 
  [DEBUG] Trying to add links for dependencies...
  [ERROR] ProjectBuildingException xxxx: Error resolving project artifact:
  </code></pre>
  
  <ol start="2">
  <li>Case 2.10.4</li>
  </ol>
  
  <p>[</p>
  
  <pre><code>[DEBUG] Trying to add links for dependencies...
  [DEBUG] Using mirror central-mirror XXX for central XXX.
  [DEBUG] Connection request: [route: {}-&gt;XXX][total kept alive: 0; route allocated: 0 of 2; total allocated: 0 of 20]
  [DEBUG] Connection leased: [id: 0][route: {}-&gt;XXX][total kept alive: 0; route allocated: 1 of 2; total allocated: 1 of 20]
  [DEBUG] Connecting to XXX
  [DEBUG] CookieSpec selected: best-match
  [DEBUG] Auth cache not set in the context
  [DEBUG] Target auth state: UNCHALLENGED
  [DEBUG] Proxy auth state: UNCHALLENGED
  [DEBUG] Attempt 1 to execute request
  [DEBUG] Sending request: GET /snapshot-site/...
  </code></pre>
  
  <p>My observations:
  In 3.0.1 case, the plugin fails to retrieve the information from the correct repo. In 2.10.4 case, the Sending request was having the correct snapshot-site url.</p>