Add tracking for YouTube videos #2156
minor fixes
Fix Bug #949510 - Add save buttons to bottom of page

Added copies of save/edit/discard etc. buttons to bottom of the page between review and attachments.

Made the buttons position:static so they wrap on mobile devices. Tweaked positioning of attachments add button to look good next to page buttons.
Now without merge conflicts with tracking.

Refactored to make page buttons into a macro.
Fixing positioning of bottom buttons on translate page
Simplify registration page copy

Because we no longer offer the "Forgot Password" form, the only function
of the page is registration. The page title is updated to reflect this
and the "New MDN Members" heading is removed.

Other changes are made, mostly minor. The Bugzilla link is removed -- we
only receive about one report per month, so it seems unnecessary to
burden all users with this notice. People who deeply care about getting
their old accounts back will likely submit a bug with or without this
notice.
Move tabzilla lower in priority, less blocking styles
fix bug 1034139 - development docs should refer to the working test subset
Merge pull request #2507 from stephaniehobson/BUG-949510-save-at-bottom

Fix Bug #949510 - Add save buttons to bottom of page
Merge pull request #2477 from iakshay/youtube-analytics

Add tracking for YouTube videos #2156
Merge pull request #2506 from openjck/register-copy

Simplify registration page copy
Merge pull request #2531 from darkwing/tabzilla-move

Move tabzilla lower in priority, less blocking styles
Merge pull request #2533 from jwhitlock/dev_docs_1034139

fix bug 1034139 - dev docs should refer to the working test subset
Add Optimizely hooks to all login buttons
Add in-source comments about Optimizely hooks