Bug 878448 - Use new mail address for German contribute form

Update contribute mail address for German form on Get Involved page.
Merge pull request #936 from flodolo/bug-878448-new-mail-de

Bug 878448 - Use new mail address for German contribute form
Add GA track to /firefox/firstrun/ newsletter. Bug 880263.

Remove WebTrends code from email_newsletter_form macro.
Add ability to monitor tabzilla usage bug 832375
Merge pull request #883 from alexgibson/add-ability-to-monitor-tabzilla-usage-bug-832375

Add ability to monitor tabzilla usage bug 832375. Add 'Partner' link to tabzilla 'Get Involved' section bug 880000.
Merge pull request #959 from jpetto/bug-880263-firstrun-newsletter-ga

Add GA track to /firefox/firstrun/ newsletter. Bug 880263.