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

This reverts commit 9dce767f90781c0b44eca6f3697da01480e8791d.
Revert "[1/2] Settings: SeekBarPreferences tweaks"

This reverts commit cac47db28aa0a9acb02209e95af79f0b84095e46.
Merge branch 'head' into kitkat

Conflicts:
	res/values/custom_strings.xml

Change-Id: Ifc073b85b62f7bf555cded28cf0d33b06c13a65e