Bugfix - initializing dc flag
Merge pull request #29 from suttonpd/master

Bugfix - initializing dc flag
Adding prach for uplink - supports preamble formats 0-3, does not currently support high-speed flag, benchmark not yet implemented
Using factor of average instead of absolute detection threshold, added fixes for high-speed sequence generation (detection still not supported), added tests for multiplexed PRACH sequences
General cleanup - moving prach code to phch folder, moving common ret vals to config.h, renamed phy_common files
Merge pull request #32 from suttonpd/master

PRACH support