Updated to use AndroidIBeaconLibrary-0.7.6 - fixes BlueToothService crashes

0.7.6 includes the BluetoothCrashResolver module, which recovers from
and prevents BluetoothService crashes dus to Android Bug 67272.

http://developer.radiusnetworks.com/ibeacon/android/releasenotes_0_7_6.html

https://github.com/RadiusNetworks/bluetooth-crash-resolver/blob/master/app/src/main/java/com/radiusnetworks/bluetooth/BluetoothCrashResolver.java