minor #1136 Add docblock for the $app field (JPry)
minor #1136 Add docblock for the $app field (JPry)

This PR was submitted for the master branch but it was merged into the 1.2 branch instead (closes #1136).

Discussion
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Add docblock for the $app field

Add a docblock to the `$app` field variable, to help out IDEs.

There's not much else to say on this one :)

Commits
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33edafe Add docblock for the $app field

arduanov/Silex,gencer/Silex,arduanov/Silex,mathroc/Silex,SpacePossum/Silex,SanderKnape/Silex,Incognito/silex-fork,jdreesen/Silex,Incognito/silex-fork,romainneutron/Silex,mmauri04/Silex,mTorres/Silex,lokhman/Silex,RayRutjes/Silex,cgsmith/Silex,SanderKnape/Silex,RayRutjes/Silex,beealone/Silex,fhinkel/Silex,mTorres/Silex,plotek/Silex,Xephi/Silex,romainneutron/Silex,silexphp/Silex,SpacePossum/Silex,beealone/Silex,jdreesen/Silex,Xephi/Silex,fabpot/Silex,cgsmith/Silex,fabpot/Silex,mmauri04/Silex,romainneutron/Silex,cesarmarinhorj/Silex,plotek/Silex,mathroc/Silex,fhinkel/Silex,cesarmarinhorj/Silex,lokhman/Silex