Update comment in lwan_thread_shutdown()

epoll_wait() will always timeout every second if there are items
in a respective thread's death queue. Previously it would wait until
lwan->config->keep_alive_timeout seconds, but this changed ages
ago.
Pass base 0 to strtol() in parse_long()

The correct base should be guessed from the contents when base 0
is passed to strtol(), so yanking the base detection code is safe
(except for binary base, which is kind of useless anyway, given
hexadecimal values are allowed).
Move module name to lwan_module_t structure
Fix crash after 824d825