[settings] long press back to kill configurable timeout (2/2)

1 - 2 seconds (default)
2 - 1,5 seconds
3 - 1 second
4 - 0,5 second

Forward ported from crDroid kk
[Settings]: recents panel clear all button tweaks

- Show or hide recents button
- Place the button in top right or left

@cristianomatos

Conflicts:
	src/com/android/settings/cyanogenmod/StatusBarSettings.java
Fix compilação [1/2]