battery saver mode: updates (2/2)

credits Yanuar Harry<ai.the.smarties.physics@gmail.com>

Change-Id: Ibf4f99f88367a68871f91344b503101a0c63bf8c
Signed-off-by: Dan Trifan <jimsth@gmail.com>
Make navbar height+width more reasonable.

Change-Id: If6fb1f75dfd64a3c9dc594232ae395bdbaf1a43b
Add a value TextView to the navbar height prefs

Change-Id: If3e62f2c6ebe1fffb2b5fe8650506e1fdae906d2
Navbar Height: Use the slider max and a min value to define the percentage range

Change-Id: Ib42a8c135179a2fe6fa673c5a50f8c1bb8ae394f