Merge pull request #52 from KimJeongYeon/master

jack2 supports android devices & rebase current changes to master
Correct XCode project NetJack2 options.
Cleanup.
More libjacknet API more robust.
Merge pull request #53 from KimJeongYeon/master

additional code cleanup for jack android
Merge branch 'master' of github.com:sletz/jack2
Typos.
Back to CELT encoder.
fix alsa driver build on non-android

4a94e12986b7f4925b0d457af8c3464ffbef2e2b broke it.

github close #54
Improve default input/ouput device selection in JackCoreAudioDriver.