Example notebooks updated.
Converted tabs to spaces
Added `update_children` pattern to remaining parent widgets
Revert 2853eb41 's changes to traitlets
Fixed JS tests to reflect Jason's changes
renamed:    wigets_container.js -> widgets_container.js
Added ViewWidget
Re-decoupled comm_id from widget models
Removed console.log, unused
Further indentation cleanup
Fixed indent of line 450
... caused Travis to get mad
Moved view widget into widget.py
Fixed indentation in widgetmanager.js
Added line to dump page html casperjs
Enabled IPython Server output for Travis debugging
Fixed static_url call which is no longer optionally 1 param
Revert "Added line to dump page html casperjs"

This reverts commit 7091ce87f7a280dde7724d92fd542b834f764e61.
Revert "Enabled IPython Server output for Travis debugging"

This reverts commit eb7ee3f61335a7147fcfc1b1907d41f163bb0b41.
deleted:    wigets_container.js
Print cell output