Settings: Simplyfiy expanded desktop summary

There is no need to have an extra summary string to display the
state of the expanded desktop mode. This commit removes the unneeded
strings and uses the entries as summary.

Change-Id: Ia7e99ec52577c64d786ef5a0117fb33f5af671ab

Conflicts:
	res/values/strings.xml
Settings: disable expanded desktop on power menu disable

If expanded desktop is enabled while the option for expanded desktop
setting is disabled, expanded desktop will remain active and the user
will not be able to disable expanded desktop without reenabling the
setting.

Change-Id: Ia91e34e5ce9f8680f64b81e5f79c2df6f0639bb2
Settings: removed "Status bar visible" expanded desktop setting for devices without navbar

On devices without navigation bar, expanded desktop is only useful
for hiding the status bar when the apps don't hide them.
"Status bar visible" setting is a no-op.

Change-Id: I16a31ec6e10c7ed11600e3b1a1d9b631f31af55e

Conflicts:
	res/values/arrays.xml
Settings: use checkbox for expanded desktop setting for devices without navbar

On those devices, there are only two settings an a checkbox would fit better.

Change-Id: I394736dacf7765f7fdda47d6d743d7479bd4de7e

Conflicts:
	res/values/arrays.xml
Settings: Separate Expanded desktop from Power menu settings

This commit separates the ability to configure the Expanded desktop
mode from the ability to enable the switch in the Power menu.  This
will allow for the ED Tile to be hidden if the feature is disabled
and the power menu entry to be removed if the user chooses to use the
Tile instead.

Change-Id: I3d2eabde8087d25940cbb1e5262086b9c6e291f1

Conflicts:
	res/xml/system_settings.xml
	src/com/android/settings/cyanogenmod/SystemSettings.java