Changes

* Landed infinite scrolling [https://github.com/mozilla/activity-stream/issues/417 | #417]* In Review - In-line youtube/vimeo embedding [https://github.com/mozilla/activity-stream/pull/755 | #755 ]

* Auto complete in search (regression from about:newtab) [https://github.com/mozilla/activity-stream/pull/765 | #765 ]* Delete/Hide/Block Improvement [https://github.com/mozilla/activity-stream/pull/778 | #778 ]* Improve first run experience [https://github.com/mozilla/activity-stream/pull/778 | #669 ]* replace about:home [https://github.com/mozilla/activity-stream/pull/778 | #724 ]* (stretch goal) Filtering in Timeline [https://github.com/mozilla/activity-stream/pull/416 | #416 ]