introduced command.js
Fixed 404 on case-sensitive file systems.
Copy files in the img folder to the build path.
Added different scaling modes for background image.
command.js
Merge remote-tracking branch 'origin/master' into cmd
Merge remote-tracking branch 'visualIDE_yj/master' into cmd
Merge branch 'master' into cmd

Conflicts:
	js/command.js
Separated the concerns for the DragDrop Functionality and the Temporary command data.

Added a button to remove all commands from the user procedure list.
Refactored code.
Merge branch 'master' of github.com:chewonit/cs3213-visual-ide-team20
Merge remote-tracking branch 'origin/cmd'
Hooked up the commands population to the new commands data.

Beautify the commands descriptions.
Changed the ordering of the assignment so the object will not be undefined.
Changed the run button position.

Show the save and load button only when user is logged in.
Removed YUI dependency.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	index.html
	js/main.js