merge with master

common/lib/xmodule/xmodule/js/src/.gitignore

-# Please do not ignore *.js files. Some xmodules are written in JS.
+# Ignore .js files in this folder as they are compiled from coffeescript
+# For each of the xmodules subdirectories, add a .gitignore file that
+# will version any *.js file that is specifically written, not compiled.
+*.js

common/lib/xmodule/xmodule/js/src/capa/.gitignore

+!imageinput.js
+!schematic.js

common/lib/xmodule/xmodule/js/src/graphical_slider_tool/.gitignore

+!*.js

common/lib/xmodule/xmodule/js/src/poll/.gitignore

+!*.js

common/lib/xmodule/xmodule/js/src/sequence/display/.gitignore

+!*.js

common/lib/xmodule/xmodule/js/src/videoalpha/display/.gitignore

+!html5_video.js