Rename "collapse" directive to "ag-collapse"

- In preparation for using angular-ui-bootstrap, to avoid a naming collision.
Added ui-bootstrap to project

- Added as project dependency
- Added to landing page
- Added as angular app dependency
Refactored input filter help modal to ui-bootstrap

- Pass $modal to input filter controller; create a scoped function for raising
  the help modal.
- Refactor the help modal template to remove extraneous markups.
- Remove modal dialog template from index page.
- Add ui-bootstrap templates to index page.
Refactored content negotiation modal

- Remove extraneous markup in modal template
- Define `help()` function in scope for opening modal
- Update info button to call `ng-click="help()"`
- Use `ng-click="$close()"` to close modal
- Remove modal from index page
Refactored cache/fs permissions modals

- Removed directives, and replaced with controllers. Controllers invoke the
  appropriate service, and, if necessary, open a modal using `$modal`. The
  modals are marked to not allow closing in any way (keyboard, clicking outside
  modal, no buttons present).
- Removed extraneous markup from modal templates.
- Updated index page to load controllers instead of directives, and to define
  ng-controller directive markup.
Refactored "create new API" modal

- Split list/create api into separate controllers; create api controller is
  attached to sidebar view of api state.
- create api controller triggers forced update of ApiRepository.getList, as well
  as api list controller on successful creation
Removed unused ag-modal-dismiss directive
Rebuild UI distribution
Merge branch 'feature/ui-bootstrap'

Switched over from bootstrap's JS to angular ui-bootstrap. Only pieces that did not work "out-of-the-box" were the modal dialogs; updated those to work with ui-bootstrap, which resulted in smaller footprint for the initial page call, and more control over the modals overall.