Settings: remove force overflow button

As of KitKat, the overflow button is always shown regardless of if
a physical menu button is present or not.

https://android.googlesource.com/platform/frameworks/base.git/+/ea04f3cfc6e245fb415fd352ed0048cd940a46fe

Change-Id: Ia05756248e9f55ac68bf31abdb7327edf6a806c4

Conflicts:

	res/values-de/cm_strings.xml
	src/com/android/settings/cyanogenmod/ButtonSettings.java
settings: bring back volume key cursor control

Framework part seems to have survived the merge.

Move volume key cursor control from language & input
to button settings.

Change-Id: Ice2b266e8fdbcdf805d36d8f2e335b569e57be65

Conflicts:

	res/values/cm_arrays.xml
	res/values/cm_strings.xml
	res/xml/button_settings.xml
	src/com/android/settings/cyanogenmod/ButtonSettings.java