Bug 960861 - mozMobileConnections should not be requisites for airplane mode

- add Radio.js
- add Radio related tests
- use this radio service in ariplaneMode
Bug 972699 - Fix unit test zero coverage when using lazy load
Bug 986504 - Use SVG badge for travis build status in README.md
Bug 986512 - Switches [BB] remove transition
Revert "Revert "Bug 971546 - [System2] Instantiable Screenshot" for possibly breaking gaia-ui tests on TBPL"

This reverts commit 60e9eb1aa68a27fa21e75264e52409aa5a2b4cc4.
Bug 971577 - [System] Make visibility manager instantiable
Merge pull request #17475 from timdream/system2-visibility-manager

Bug 971577 - [System] Make visibility manager instantiable +shepherd, r=alive
Merge pull request #17376 from timdream/system2-screenshot-land

Bug 971546 - [System2] Instantiable Screenshot, r=alive
Merge pull request #17450 from jankeromnes/svgbadge

Bug 986504 - Use SVG badge for travis build status in README.md r=me
Bug 986960 - Intermittent erroring test, should flick through images in fullscreen mode
Merge pull request #17492 from KevinGrandon/debug_intermittent_tests_fix

Bug 986960 - Intermittent erroring test, should flick through images in fullscreen mode
Bug 971554 - [System2] Instantiable SoundManager

Conflicts:
	apps/system/js/bootstrap.js

Conflicts:
	apps/system/test/unit/bootstrap_test.js
	build/jshint/xfail.list
Merge pull request #16947 from dwi2/bug976986

Bug 976986 - SettingsListener should have unobserve() method
Bug 981965 - Remove browser menu top

Conflicts:
	apps/system/style/window.css
Merge pull request #17494 from gasolin/sheriff971554

Bug 971554 - [System2] Instantiable SoundManager, r=alive
Merge pull request #17495 from gasolin/sheriff976986

Merge pull request #16947 from dwi2/bug976986, r=timdream
Merge pull request #15550 from EragonJ/bug-960861

Bug 960861 - mozMobileConnections should not be requisites for airplane ...
Merge pull request #17496 from gasolin/sheriff981965

Bug 981965 - Remove browser menu top, r=timdream
Bug 961800 - Implement Child Window Factory.

Conflicts:
	apps/system/js/app_transition_controller.js
	apps/system/js/app_window.js
	apps/system/js/app_window_manager.js
	apps/system/js/cards_view.js
	apps/system/style/window.css
Merge pull request #16891 from RickyChien/bug-972699

Bug 972699 - Fix unit test zero coverage when using lazy load r=@yurenju