Settings: Add support to enable/disable Electron Beam (2/2)

Parts were brought over from CM9 but not all of it.  This completes
the port.

Change-Id: I5ebfab22e68ea34e3babfaacd9c8103e25932d3d
Merge "Settings: Add support to enable/disable Electron Beam (2/2)" into cm-10.1
Merge remote branch 'cm/cm-10.1' into cm-10.1