Post release version bump.
[DOC release] Adds documentation for View#elementId, which somehow escaped documentation
[BUGFIX release] Allow view instance to be passed to {{view}}
Merge pull request #9883 from chadhietala/allow-view-instance-passing

[BUGFIX release] Allow view instance to be passed to {{view}}
[BUGFIX stable] Sanitize Href attribute usage.
[BUGFIX stable] Expand sanitization to img and link tags
[BUGFIX stable] Add escaping to iframe.
Merge pull request #10028 from rwjblue/href-xss-1-9

[BUGFIX release] Sanitize Attributes for a, img, link, and iframe tags.
Update changelog for 1.9.1.
Update version number for 1.9.1.
Merge branch '1.9.1' into 1.9-with-updated-rsvp
Update to 1.9.1