[2/2] Settings: Add custom periods for data usage measurement

PS4
externalize strings and minor layout tweak

Change-Id: I815f6a773375a855514bc9a6517f292ffcc157a2

Conflicts:
	res/values/custom_arrays.xml
	res/values/custom_strings.xml
Remove Custom String s..Only Illusion

Change-Id: I99af3662f66a3cd5ac41767cbe7f09397a316c8d