Bug 1009294 - http://www.mozilla.org/en-US/lightbeam/ needs several small updates

Corrections to the Lightbeam About page as described in
https://github.com/mozilla/lightbeam/issues/473

Also removes references to the database server which doesn't exist yet.
Bug 1018993 - Update style guide links to assets.mozilla.org
Fix CSS bug when selecting multiple countries. Bug 1019147.

- Slightly optimize event handling on provider link tracking.
Bug 1018724 - Tabzilla lang bar broken

A workaround for the wrong language detection due to caches, until the
header issue is fixed by CDN.
Fix Bug 1019277 - Wrong date on the ESR release overview image
[fix bug 1010519] - usage campaign add descriptive text to learn more links
Merge pull request #2068 from jpetto/bug-1019147-country-select-css-fxos-devices-page

Fix CSS bug when selecting multiple countries. Bug 1019147.
Fix Bug 1010132, improved Flash reporting for beta plus versions of Fx
Merge pull request #2073 from ossreleasefeed/bug1010132-flash13_0_0_206_incorrectly_shown_as_latest

Fix Bug 1010132, improved Flash reporting for beta plus versions of Fx
Merge pull request #2071 from kyoshino/bug-1395709-esr-image-date

Fix Bug 1019277 - Wrong date on the ESR release overview image
Merge pull request #2066 from retornam/bug-1018993-update-style-guide

Bug 1018993 - Update style guide links to assets.mozilla.org
Merge pull request #2002 from fmarier/minor_changes_lightbeam

Bug 1009294 - http://www.mozilla.org/en-US/lightbeam/ needs several small updates
Merge pull request #2069 from kyoshino/bug-1018724-wrong-tabzilla-lang

Bug 1018724 - Tabzilla lang bar broken
Merge pull request #2072 from alexgibson/bug-1010519-usage-campaign-add-descriptive-text-learn-more-links

[fix bug 1010519] usage campaign add descriptive text to learn more links