Include netinet/in_systm.h in lm-sock.c, fixes LM-130. Added check for netinet/in_systm.h and include it in lm-sock.c if it exists. It fixes a build error on BSD.

Makefile
Makefile.in
lm-change-password
lm-register
lm-send-async
lm-send-sync
test-http-proxy
test-lm
test-tunnel
*.swp