Revamp DSP Manager

Adds drawer navigation to the DSP Manager.
Drawer navigation is default, but it also allows to switch back
to the old view pager (tabbed) navigation.

It also allows to enable/disable drawer mode, enable/disable
tabbed mode and enable/disable the option to switch between
these two navigation modes.

General code cleanup and formatting is done as well.

Video Preview:
https://www.youtube.com/watch?v=w63YscJ_WCo

Change-Id: I43ca72809255acf2442dd2c716232587ea23237e