Revert "Bug 897352 - [gaia build system] Transition to a build_stage for assembling apps"

This reverts commit 22a4d4f8065af46d23097bbaf898831d5c031ce3.
Merge pull request #17362 from alivedise/bugzilla/983290_master/orientation-hidden

Do not display perpendicular app on opening, r=timdream
Bug 897352 - [gaia build system] Transition to a build_stage for assembling apps

Conflicts:
	Makefile
	apps/communications/build/build.js
	build/copy-build-stage-manifest.js
	build/test/integration/distribution.test.js
	build/utils-xpc.js
	build/utils.js
	build/webapp-manifests.js
Bug 972699 - Fix unit test zero coverage when using lazy load
Merge pull request #17348 from qdot/985795-contact-utils-misc-unit-test-fix

Bug 985795 - Only patch required single utils function versus mocking object
Merge pull request #17360 from prcxuying/bug972308

Bug 972308 - Re-use the existing Audio object when playing keypad tones r=gsvelto
Bug 963556: Update NFC Manager, Handover to use new shared nfc_utils.js.

Conflicts:
	apps/system/js/nfc_handover_manager.js
	apps/system/js/nfc_manager_utils.js
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 #17363 from yurenju/stage2

Bug 897352 - [gaia build system] Transition to a build_stage for assembl... r=@ochameau
Bug 984574 - JSHint fixes. r=kgrandon
Bug 985090 - Fix voicemail number migration issue and refactor
Merge pull request #17369 from yurenju/nfc

Bug 963556: Update NFC Manager, Handover to use new shared nfc_utils.js. r=@alivedise
Bug 980344 - [FTE] Fixed some jshint errors
Merge pull request #17370 from alivedise/bugzilla/961800_master_merging/child-window-factory

Bug 961800 - Implement Child Window Factory, r=etienne
Bug 981401 - [Messages] Notification does not vanish when the SMS is read when going back from sleep
Revert "Bug 897352 - [gaia build system] Transition to a build_stage for assembling apps" for Breaking Windows Builds

This reverts commit 91c8fd2a33c9be6a745a3f30a6e5113831655502.
Merge pull request #17330 from steveck-chung/bug-981401

Bug 981401 - [Messages] Notification does not vanish when the SMS is read when going back from sleep. r=arcturus
Bug 984251 - ./bin/gaia-test and Travis-CI unit tests should be working with test_apps
Revert "Bug 961800 - Implement Child Window Factory" for Gaia UI Test Bustage

This reverts commit 0cd5228663d8563831f0156e85ae8225d2004a3c.
Bug 981882 - Update input field design