note on coap_read removal: as the lwip implementation currently launches
the package handling right from the recv callback, a coap_read function
is not meaningful (as it is in posix or contiki where it actively
fetches the messages from the network buffer).
This drops the cumbersome mintapif mechanisms from server.c, fixes
header troubles that have popped up probably during the header cleanups,
drops old workarounds and enables IPv6.
* resolve file resolution conflicts between lwip and libcoap in favor of
lwip by rearranging the makefile
* cover the config.h of a configured base libcoap with the local one
using the deprecated -I- gcc switch
* enable etharp (no idea why it wouldn't work ootb, the complete
server.c lwip-contrib copy needs to be reviewed)
* disable optimizations for easier debugging, enable -g3 for macro
expansions
chrysn