feature(test): Add a front end code coverage task - `grunt coverage`

* Use blanket as the coverage reporter.
* Install `grunt-blanket-mocha` to handle reporting results to grunt.
* Set up new grunt task, `grunt coverage` for reporting.
* Add more front end tests where coverage was lacking.
* Hook up code coverage results to the intern by running tests in PhantomJS
* Only enable code coverage if explicitly requested
* Only enable front end tests in dev mode.
* Fix code that gave PhantomJS problems (Function.prototype.bind)
Commit from Mozilla Verbatim by user tomer@gmx.net.: 80 of 114 strings translated (1 fuzzy).
fix(l10n): use underscores instead of dashes in locale directory names; enable all locales on dev
Commit from Mozilla Verbatim by user steekid.: 114 of 114 strings translated (0 fuzzy).
Merge pull request #613 from mozilla/issue-610-rename-locales

fix(l10n): use underscores instead of dashes in locale directory names; ...
Merge pull request #603 from mozilla/issue-403-code-coverage

feature(test): Add a front end code coverage task - `grunt coverage`
fix(client): Add /signin_complete endpoint.

* Send verified users there after successful sign in.

Closes #546
fix(build): Use static version numbers for bower deps
fixes(build): Adds missing copyright header
Adding l10n-create-json task and moving copyright task
Merge pull request #621 from mozilla/issue-546-signin-complete-screen

fix(client): Add /signin_complete endpoint.
Merge pull request #627 from pdehaan/issue-626

refactor(build): Adds missing copyright header
Merge pull request #629 from pdehaan/issue-628

fix(build): Adding l10n-create-json task and moving copyright task
Adding explicit Git hashes for a few modules
feat(client): update document title on screen transition.

* Look for h1 and h2 elements in the view. Use these to set the title.
* If no h1 or h2 element, use the startup page title.

Closes #531
Merge pull request #623 from pdehaan/issue-622

fix(build): Use static version numbers for bower deps

lgtm. Tests all still pass. Manual testing looks good. 

r+ - thanks @pdehaan!
feature(contributors): Adding CONTRIBUTING and CONTRIBUTORS files
Update README.md
Merge pull request #635 from pdehaan/issue-630-take2

feature(contributors): Adding CONTRIBUTING and CONTRIBUTORS files

Beautiful! r+. A great follow on would be to call `npm contributors` during the grunt build task. Thanks for working through this with me @pdehaan!
fix(server) render index.html on the server for l10n.

* Went down a grunt and requirejs rabbit hole - updated requirejs, grunt-contrib-uglify, grunt-usemin deps that contain bug fixes.
* index.html rendered on server side to allow for <noscript> translations.
* Update useminPrepare task to look for resources in both client side and server side rendered templates. Note: grunt-usemin no longer supports requirejs based resources. These resources must now be generated independently.
* Update uglify task to search for js to compress in the <%= yeoman.tmp %> directory instead of overwriting files in the dist directory.
* Update requirejs task to generate almond based output.
* Use an almond based main.js in production instead of using requirejs.

Closes #286
Closes #556