Android: Don't display "null" as artist.

git-svn-id: http://svn.code.sf.net/p/subsonic/code/trunk@3468 104adb81-38d2-4886-885e-82898e39ce25
Android: Use native video player (incomplete)

git-svn-id: http://svn.code.sf.net/p/subsonic/code/trunk@3469 104adb81-38d2-4886-885e-82898e39ce25
Android: Added video player setting.

git-svn-id: http://svn.code.sf.net/p/subsonic/code/trunk@3470 104adb81-38d2-4886-885e-82898e39ce25