Set version to 1.4.6-SNAPSHOT
Issue #161: Fix IllegalState with Menu Drawer ListView adaptor

When returning the Menu Drawer list view could be in a wrong state so
repopulate the options available when the application is restarted to be
on the safe side.
Refactor External Player support.

This change refactors the external player support.  This provides some meta
data around the supported external players and their functionality.  In
addition users can specifically select the external player from the list
of supported players.  The System Default player can be used as well.
Release 1.4.6
Merge branch 'hotfix_issue_161'