Fully remove ModalController

Commit 1699b56ead70e0c8072c5edf3d634324202c1d58 removed most references to
ModalController, but left a few intact. This removes the remaining two
references so the page resumes loading.
Fix spelling of "filters"
Accept the principal on the commandline

When --server-principal is passed to Grunt, we want to actually request tickets
for that principal, instead of continuing to hardcode it in the Webathena
ticket request logic.
Fix quoting messages in private conversations

Quote-replying to messages in private conversations should stay in that
conversation, not go to -c message -i personal ''.  This fixes that.
Merge pull request #63 from dehnert/roost-2-init

Minor fixes
Fix multiple small bugs

Fix issues with filter display, message display, filter updating, and saving state.
Fix scrolling up while loading cached messages.
Merge branch 'roost-2-init' into compositing

Conflicts:
	app/coffee/model/RoostSession.coffee
	app/coffee/view/MessagePane.coffee
Fix case where the screen is narrower than 600px.