Add quick pull down for quicksettings.
Expose quick settings category only on phones.
Ported code from cm:
https://github.com/CyanogenMod/android_packages_apps_Settings/commit/57a8fb52eca6bda33d167d378374c98d9415e66c
https://github.com/CyanogenMod/android_packages_apps_Settings/commit/8453209cc94ce136113d70319e757e2e3c150988

fix wrong key for quick_settings_category