Use rootURL to fix some path issues.

You knew this should work, but there is a bug in Ember pre4 where it
wasn't working.  Manually patched.  The fix should be in on the next
version:

https://github.com/emberjs/ember.js/pull/1836
Better handling of boards view.

I didn't know about "render" and so I ended up using nested routes to
get the new form to show up.
Improve new slide setup.

Same as an earlier commit where I didn't know about render and hooked
things up lamely.
Use model instead of content.

It's what peepcode uses, so I assume it's what the core guys think you
should use.  Also, it makes it more obvious that I should be using the
"model" method in the routes.
Switch to requiring postgres.

I'm going to remove the configured attribute classes and all that noise
and replace it with hstore.  While staying database agnostic would've
been nice, I can replace a bunch of code and maybe even drop redis if I
use psql.
Use hstore for Source configuration.

Still haven't removed the ConfiguredAttribute model for this, since the
PerspectiveAssignmentConfiguredAttributes are still using it.
Replace PerspectiveAssignmentsConfiguredAttribute with hstore.
Only test HstoreConfiguration in one place.

I was testing the same behavior in the two classes that include the
module.