Bug 964342: Send language setting to basket.

* Add error codes to basket client.
* Use error code for invalid email instead of looking for a message.
* Add timeout handling for call to basket.
Bug 963445 - [UITest][API] refactor tests using Building Blocks
Bug 964517 - Add solid background to apps where appropriate. r=alive
Bug 974261 - Volume buttons stucks, need clearTimeout()
Bug 952611 - Disable intermittent tests
Merge pull request #16469 from KevinGrandon/bug_952611_disable_failing_tests

Bug 952611 - Disable intermittent tests
Bug 958340 - Download node_modules from github
Merge pull request #15319 from KevinGrandon/bug_958340_node_modules_prototype

Bug 958340 - Download node_modules from github
Merge pull request #16436 from timdream/system2-hardwarebuttons-fix

Bug 974261 - Volume buttons stucks, need clearTimeout() +shepherd
Bug 973787 - [Gaia] SD card formatting: reword message and appearance of the format button

New main string suggested by :matej
Disable regressed email tests r=asuth
Disable python persona cookies
Bug 953093 - [Fugu][File upload selector] Choosing the system ringtones will go back to the webpage
Merge pull request #16494 from gaye/disable-broken-email-tests

Bug 974564 - Disable regressed email tests r=asuth
Bug 971371 - Remove all test/integration directories from gaia
Merge pull request #16430 from theres-waldo/master

Bug 964517 - Add solid background to apps where appropriate. r=alive
Merge pull request #16385 from flodolo/bug973787

Bug 973787 - [Gaia] SD card formatting: reword message and buttons
Bug 974292 - [Email][V1.3&V1.4] Tapping the Done button of mail settings page redirects to a blank page
Merge pull request #15669 from MBRSL/bug-963445-API

Bug 963445 - [UITest][API] refactor tests using Building Blocks
Merge pull request #16253 from pmclanahan/send-language-to-basket-964342

Bug 964342: Send language setting to basket.