Deal with ansi escape codes when nbconverting to latex

Correctly deals with "reset" codes and short codes.  Interprets blinking
style as bold.
Added widget output area
Add widget subarea style
Added dependencies to page.html template and added widget.js to notebook.html
Added widget.js
Added widget.py
Added widjet.js
Other commit actually added notebook.js changes
Fixed widget.js and notebook.js so IPython.notebook.widget_manager is created.
Fixing infinite recursion.
Added apply method to base model.
Allows model to propogate changes to all views except
for the one specified.
Added display hook logic to handle widgets
Basic display logic
s/show/_repr_...
Added code to display Javascript in frontend.
Moved widget.js into widget code directory
Added utility function to send all the javascript
in the current directory to the frontend.
Updates to widget.py
Added global init js function
Moved init comm logic to show function
Widget Display logic
Added clear widget area button
Clear widgets upon cell execute
Adjust weidget box so widget_subarea aligns with codecell
Handle widget hide/show logic
also only create a widget manager once