Session management and bug fixes.

- Login is now on a per session basis using a session cookie.
- Many small bugs that were introduced by switching to the N4J
  class have been fixed.
Merge branch 'master' of heroku.com:radiant-island-6246
Added a view that displays a network of ideas

1) Added method in N4J to collect all connections (not a thing for the future)
2) Added template for a SVG depiction of the graph using d3js (network.html)
3) Connected url /network/ to the network view
Merge remote-tracking branch 'origin/master'

Conflicts:
	bulb/urls.py
	bulb/views.py