Add option to reset battery stats (1/2)

Thanks to CyanogenMod and @jruesga
Live Volume Steps [2/2]

-Volume steps changes are instant, no need to reboot!

LiveVolumeSteps: transitioned volume steps volume normalization.

-This calculates an equivalent volume ratio for the new
volume steps.
-example: Volume steps are set at 60. Volume is set at 5. That is
very low volume. Then volume steps are switched to 5. Now you
are instantly in a state were your volume steps are 5 and your
volume is 5. That's full volume! This fixes that issue.
-So it basically keeps the volume from jumping around while your
changing volume steps. It may be a little lower but should be
very close.

Change-Id: I4ca587e0bd3eed381e019023176cfce3ec5c0b80
Signed-off-by: STELIX <ssspinni@gmail.com>