Add support of netmap as a capture module

The compilation error is:
/home/flahoudere/workset/haka-orig/lib/haka/luadebug/user_remote.c: In function ‘print’:
/home/flahoudere/workset/haka-orig/lib/haka/luadebug/user_remote.c:216:11: error: ignoring return value of ‘vasprintf’, declared with attribute warn_unused_result [-Werror=unused-result]
  vasprintf(&line, format, args);
           ^
/home/flahoudere/workset/haka-orig/lib/haka/luadebug/user_remote.c: In function ‘luadebug_user_remote_server_session’:
/home/flahoudere/workset/haka-orig/lib/haka/luadebug/user_remote.c:357:9: error: ignoring return value of ‘write’, declared with attribute warn_unused_result [-Werror=unused-result]
    write(fd, &command, 1);
         ^
cc1: all warnings being treated as errors
make[2]: *** [lib/haka/CMakeFiles/libhaka.dir/luadebug/user_remote.c.o] Erreur 1
make[1]: *** [lib/haka/CMakeFiles/libhaka.dir/all] Erreur 2
make: *** [all] Erreur 2
I am not sure it's better in a makefile, that means that the param needs to be added to all build (we don't know who includes that file, so we can't put it just on some packages) and it's not a param that could be disabled to change configuration (it adds a whole bunch of helper functions that are needed to compile the netmap module