1. add new example for A2DP and the related btif layer source code is ported
2. modification on osi_alarm_new API to support periodic timer
3. enable macro BTA_AR_INCLUDED, BTA_AV_INCLUDED, BTA_AV_SINK_INCLUDED
4. The A2DP example cannot work and can only be built successfuly
1. move the app demo code to example
2. move the header files to correct path
3. move profile to profiles directory and seperate esp&std
4. some other codes
5. needs continue to cleanup the code