Bug 882346 - Add dom.experimental_forms pref

Conflicts:
	build/preferences.js
Bug 864751 - Add profile directory define

Conflicts:
	Makefile
	build/settings.py
Catchup makefile from master
Bug 848604 - used apps.list to pick apps from apps/*, external-apps/* & GAIA_DISTRIBUTION_DIR

Conflicts:
	.gitignore
Bug 879563 - Added option for installing external addons. r=ochameau

Conflicts:
	Makefile
Update browser extensions from master
Revert "Update browser extensions from master"

This reverts commit 6d6fa53b8128e5621b31e59329c643f78fcc3cf2.
Bug 893188 - Update system message manager
Merge master webapp.zip.
Merge pull request #90 from KevinGrandon/haida

Fix content branch makefile