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.