Add Themes category

Under Personal category

Change-Id: I0eb669956d9e89bb92cd43487b14b4246454a400
Signed-off-by: ayysir <dresadd09691@gmail.com>

Conflicts:
	res/values/strings.xml
	res/xml/settings_headers.xml
Merge branch 'offpa/ThemeEngine'

Signed-off-by: ayysir <dresadd09691@gmail.com>

Conflicts:
	res/values/strings.xml
Merge branch 'jb43-legacy' of https://github.com/ParanoidAndroid/android_packages_apps_Settings into jbl43