title: How to get tools/source.properties on Android SDK (in Travis)?
body: <p>I'm trying to build <code>javaocr</code> on Travis and <a href="https://travis-ci.org/krichter722/javaocr/builds/178875130" rel="nofollow noreferrer">the <code>com.simpligility.maven.plugins:android-maven-plugin:4.1.1</code> Maven plugin wants to read <code>tools/source.properties</code> in the Android SDK root</a>. How can I provide this file? I cannot install the complete SDK since it will exceed the space limitation of the Travis CI service, but I'm sure there's a specific component which needs to be installed.</p>
  
  <p>I have no idea about the Android API version or whatever is needed, but I'll figure it out if necessary. My current motivation is to verify the complete project on Travis after I made changes to it.</p>