refactor(client): Remove global variables in fxa-client.js

* Replace the global variables in fxa-client.js with instance variables.
* All view tests create their own fxa-client to avoid cross test pollution.
* One fxa-client instance is shared across views for the application.

Work done as part of the evaluation of the amount of work to replace fxa-js-client with a mock for testing. (See #1356)

fixes #1304
tweak(styles): sassify font sizes
Merge pull request #1375 from mozilla/issue-1369

tweak(styles): sassify font sizes
Merge pull request #1363 from mozilla/issue-1304-no-globals-fxa-client

refactor(client): Remove global variables in fxa-client.js
chore(dep): Update Bower to 1.3.8
Merge pull request #1385 from vladikoff/bower138

chore(dep): Update Bower to 1.3.8
fix(fonts): Update connect-fonts-firasans and grunt-connect-fonts.

* Upgrade connect-fonts-firasans which now uses font version 3.111 to fix font rendering issues in IOS.
* Upgrade to grunt-connect-fonts fixes SVG font search parameter problem.

issue #1267
fixes #1382
Merge pull request #1384 from mozilla/issue-1267-update-fonts

fix(client): Update connect-fonts-firasans and grunt-connect-fonts. Fixed #1267
fix(legal): fix rendering of legal pages when loaded directly via url

Fixes #1372.
fix(l10n): use correct locale if specified in url for legal pages

Fixes #1337.