High priority fixes

* Helpful/unhelpful did not work; JS error (var id was not set)
* Renamed "Hide" to "Hide this post"
* Autohide did not trigger mask and had some missing i18n
* Unrequest oversight should not trigger tipsy
* Hide content when AFTv5 isn't active on any namespace
* Offset 0 is also valid; only false should not set offset
* Improved display of "Hide my post"
* Fix typo "usepful"

Change-Id: I16491a1af5c460a72481d32cfc7fbd44ecb9d836
Merge "High priority fixes"