* 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
* trx_toolkit/data_msg.py: enrich some ValueError messages
* trx_toolkit/data_msg.py: also print burst length in desc_hdr()
* trx_toolkit/data_msg.py: fix: make sure header version is known
* trx_toolkit/data_msg.py: fix message length check in parse_msg()
* trx_toolkit/data_msg.py: legacy flag is only for version 0x00
* trx_toolkit/data_msg.py: introduce header coding version 0x01
* trx_toolkit/data_msg.py: implement header version coding