Build list of AWS regions for region selector.  GUI-74
Better way to set and detect aws_enabled flag.
Initial progress fetching instances from AWS.
Add connection manager and simplify fetching Instances on landing page. GUI-74
Add a cached connection manager rather than storing the connection object in a memory-based session and revert to cookie-based sessions, both for compatibility with gunicorn (multi-core support) and high-availability configs.  Pull instances from the view rather than the Instance model to stick with Boto conventions.
Add Beaker cache config settings to console.ini.
Wire up Euca connection object.  Allow clcport to be configurable in console.ini, defaulting to 8773.  Move connection object fetches to BaseView class to keep things DRY.  Pull instances from Euca backend.  GUI-74
Add docstrings to connection manager methods.
Enable AWS region selection.  GUI-74
Merge pull request #2 from eucalyptus/GUI-74

GUI-74: Instances landing page