Fix ckeditor-init.js by giving it access to a valid jQuery instance, along with other minor changes to ckeditor-init.js

fixes #13 . Previously ckeditor-init.js failed to properly run as '$' was undefined. The fix is to use django's jQuery instance if '$' is undefined. 

Also, I replaced the .click() with a .on() because I was running into issues with the event being attached before all elements had been placed. This is particularly an issue for users of django-nested-inlines.

#### Changes:
- Set $ to django.jQuery if $ not defined
- organize ckeditor-init.js
- replace .click(...) with delegated .on(...) in case elements do not exist when code is run