Narrow grunt jshint scope to js development folders
Narrow grunt jshint scope to js development folders

Currently, when running grunt, the jshint step chokes on the Grunt-
generated JavaScript in app/src/main/assets.  The check should be
confined to the folders where we actually do our JS development.

Change-Id: I8939e1b9e3b53eb084fdac18aee858e9c87805df

carloshwa/apps-android-wikipedia,carloshwa/apps-android-wikipedia,anirudh24seven/apps-android-wikipedia,Duct-and-rice/KrswtkhrWiki4Android,SAGROUP2/apps-android-wikipedia,wikimedia/apps-android-wikipedia,dbrant/apps-android-wikipedia,SAGROUP2/apps-android-wikipedia,SAGROUP2/apps-android-wikipedia,wikimedia/apps-android-wikipedia,anirudh24seven/apps-android-wikipedia,Duct-and-rice/KrswtkhrWiki4Android,wikimedia/apps-android-wikipedia,Duct-and-rice/KrswtkhrWiki4Android,carloshwa/apps-android-wikipedia,dbrant/apps-android-wikipedia,carloshwa/apps-android-wikipedia,wikimedia/apps-android-wikipedia,dbrant/apps-android-wikipedia,SAGROUP2/apps-android-wikipedia,dbrant/apps-android-wikipedia,SAGROUP2/apps-android-wikipedia,anirudh24seven/apps-android-wikipedia,dbrant/apps-android-wikipedia,Duct-and-rice/KrswtkhrWiki4Android,anirudh24seven/apps-android-wikipedia,Duct-and-rice/KrswtkhrWiki4Android,carloshwa/apps-android-wikipedia,anirudh24seven/apps-android-wikipedia