feat(rxPageTitle): Strip HTML from page title

Closes #660
test(rxPageTitle): attribute and escaped char tests
feat(rxUnsafeRemoveHTML): New filter
docs(rxPageTitle): Update README
feat(rxPage): Enable access to rxPageTitle setTitleUnsafe
Merge pull request #661 from rackerlabs/660_strip_html_from_page_title

feat(rxPageTitle): Method to optionally strip HTML from page title
feat(rxModalAction): Add defaultFocus option

Adds the ability to set default focus on the rxModalForm directive. Options for focus are 'submit' or 'cancel', anything else will give focus to the first tabbable element