Update view_all.html

fix a typo
[bug 1008667] Updates to Get Involved wording.

Update get-involved.html
Update get-involved-questions.html
Update get-involved-l10n.html
[bug 1006493] Index contribution data in ES.

This creates a new ES index for just metricsy things.

New mapping types for models that map to contributions:
* Answer (Support Forum contribution)
* Revision (KB and L10n contributions)
* Reply (Army of Awesome contribution)
[bug 984709] Add GA Experiments snippet to two articles.
[bug 1012589] Changing Username to Display name

When visiting someone's profile, the title should
appear with Profile name not Username.
[bug 570425] Fix line breaks on contributor forum