AP_GPS: Add agcCnt to UBX1 message
Frame_params: 3DR_X8+_RTF.param

Adding param file for 3DR X8+
GPS: use primary for Notification
GPS: init primary_instance to zero
AP_AHRS : Add reset of EKF gyro bias states
AP_NavEKF : Add public method to reset gyro bias states
Copter: fail to arm if gyro cal fails
Copter: re-enable CPU failsafe if arming fails
Merge remote-tracking branch 'arducopter/master'
Latest