Merge pull request #62 from teharrison/master

 	removed hardcoded key, made builder space taller
demo stuff
Merge branch 'master' of github.com:MG-RAST/Retina

Conflicts:
	widgets/widget.NotebookDashboard.js
	widgets/widget.VisualPython.js
removed duplicate (leftover from merge)
added base64 encoding / decoding functions
moved add renderer functions to the correct place
added authentication
logout will now also affect Ipy.auth
modified auth: on login or logout update all notebook iframes, add auth when new iframe created, fixed test of valid auth. added modal triggers: login on page start, dashboard on login close