[osxsink] - for devices which report samplerate 0hz - allow user overrid...

...e

with 44.1khz and 48khz

There are broken coreaudio drivers out there for third party audio hardware on osx. E.x. HarmonKardon Soundsticks.

Those report "0" as samplerate. In that case ActiveAE just crashes @fernetmenta maybe something to cure?

Long story short. For the osx sink if we don't get a valid samplerate we add 44100 and 48000 and hope the user will chose the correct setting via "fixed" configuration.

@jmarshallnz - this is the quirk for http://forum.xbmc.org/showthread.php?tid=189472&pid=1661359#pid1661359