remove write_config functionality
remove jammer_cfg struct
move macaddr parser to config.c and kill mac_address.c
fixup scanf warning from parsing with %x
cleanup old comment
move structures to wmediumd.h and cleanup leftover mac_address stuff
fixup whitespace bug
make config file loader construct the station list

Having more than one global variable holding the count of
devices seems excessive.
nuke probability.[ch]

Since I got rid of the probability matrix stuff, this was just
code to track an array of mac addresses.  This responsibility now
belongs to the station list so we can kill this stuff.
jettison more unused functions
drop all counters

Most of these aren't updated since my changes.  We can easily add
them back if wanted.
cleanup unused variables
use u8 for station mac address

Fixes:
wmediumd.c: In function ‘deliver_frame’:
wmediumd.c:234:12: warning: pointer targets in initialization differ in
signedness [-Wpointer-sign]
  u8 *src = frame->sender->addr;
            ^
use %z to format size_t
remove unreachable label
rearrange to avoid implicit function definitions
fix up two type mismatch errors

ouch, frame->sender only happened to work due to struct layout
add a prototype for get_error_prob()