Add some explicit overrides.
Bugfix. Duplicate if conditions in PeripheralController.java
front: Changed transparency setting range from [0,255] to [0,100]
front: Enhanced the SeekBarPreference implementation.

Implementation closely follows the pattern used by Android's own
EditTextPreference.

Features:
 - Dirty state is maintained on rotation
 - Attributes settable in xml or java and follow standard approach
 - Default value is specified using built-in Preference machinery
 - Seek bar snaps to values based on given step size
front: Eliminated "Hide buttons" option (redundant).

The "Touchscreen transparency" option takes care of it and much more.
Merge branch 'master' into experimental_cheatsMenu

Conflicts:
	src/paulscode/android/mupen64plusae/persistent/OptionCheckBoxPreference.java