Answer call with hardware HOME button (1/2)

Squashed commit of the following:

Author: Oleksandr Byelkin <sanja.byelkin@gmail.com>
Adds ability to answer call with hardware HOME button
preparation to winter time
Change-Id: I0d22a6fbb92a61f08b50cae5c14d0030b81ee6ec

Author: Michael Bestas <mikeioannina@gmail.com>
Settings: Move home answer & power end call options

Move 'Home answers call' & 'Power ends call' options to button settings
Change-Id: I2f365a3d278b0845b7c5ffcfe70c54160a00c24e

Conflicts:
	res/values/cm_strings.xml
	res/xml/accessibility_settings.xml
	res/xml/button_settings.xml
	src/com/android/settings/ButtonSettings.java
	src/com/android/settings/accessibility/AccessibilitySettings.java