Better diagnostics in the stagefright commandline tool, support for playing...

Better diagnostics in the stagefright commandline tool, support for playing sine-tones using a filename of "sine:[samplingrate]", i.e. sine:44100. Support for playing audio through to the speakers by using "-o" in addition to "-a".

related-to-bug: 2553359
Change-Id: Ic49eb89feb62474d9513bc21571e0e8fe3a15e0b