* trxcon: get rid of init_defaults(), init app_data in place
* trxcon: make trxcon_gsmtap_send() static
* trxcon: send proper slot type in TRXC SETSLOT messages
* trxcon: separate the scheduler into libl1sched.la
* trxcon: abstract out the scheduler API from L1CTL/TRXD/TRXC