title: Binding error with slf4j
body: <p>I am using a tool, GATE for text analysis and while installing a PR I get the following error-</p>
  
  <p>SLF4J: The requested version 1.5.6 by your slf4j binding is not compatible with [1.6, 1.7]</p>
  
  <p>Now, I have searched the internet regarding this and have found this-</p>
  
  <pre><code> Mixing different versions of slf4j-api.jar and SLF4J binding can cause problems. For example, if you are using slf4j-api-1.7.2.jar, then you should also use slf4j-simple-1.7.2.jar, using slf4j-simple-1.5.5.jar will not work.
  </code></pre>
  
  <p>I am using slf4j-api-1.7.12 , but this file- slf4j-simple-N does not exist on my computer. 
  How can I resolve this problem?
  Any help will be apprecited. Thanks!</p>