title: How include git branch name in apk file name automatically
body: <p>I'm looking for a way to include the <em>git branch name</em> into my android apk file name upon building it.</p>
  
  <p>I would like to name my apk file "ProjectName-<em>git branchname</em>.apk, automatically upon building it.
  "</p>
  
  <p>Example: "MyTestProject-master.apk"</p>
  
  <p>I've searched online and read the gradle docs but can't find a reference to how to include the branch name into the output file name.</p>
  
  <p>I know how to use gradle to construct a file name, generally speaking. I'm specifically asking about the git branch reference.</p>