Quick initial integration of software keyboard into KA Lite exercises.
Merge branch 'css_cleanup' into software-keyboard
Tweaks to styling for software keyboard.
Adding other mather notations.
Adding clear input field function.
Fixed "next question" displaying issue
Showing Numberpad
Only show the numberpad if it is an andriod device.
Fix some formats
Signed-off-by: wangguan59 <wangguan59@gmail.com>
Merge branch 'develop' into software-keyboard
Show up on all the devices.
Merge branch 'develop' into software-keyboard

Conflicts:
	kalite/static/js/khan-exercises/khan-exercise.js
	kalite/static/js/khan-exercises/utils/answer-types.js
	kalite/templates/exercise.html
	python-packages/debug_toolbar/urls.py
Moves software-keyboard to new location.
Implements first pass of Backbone driven software keyboard.
Makes numpad appear for all applicable answer types.
Merge branch 'develop' into software-keyboard
Fixes on screen keyboard to only appear for Android devices.
Removes erroneously included file.
Fixes error in less.js import.