fix a lot of issues on psogc; add proxy module

- $ann implemented
- concurrency removed; server is now single-threaded, event-driven and much more stable
- rare seed is no longer the game id; ids are sequential from server startup so they weren't random at all before
- supports dropping privileges; now you can run it as root so it can open a sockets on low ports, then it will switch to the given user before serving any traffic
- newserv now behaves like a proxy if you run it with the --proxy-destination=<IP_OR_HOSTNAME> argument; there's also an (invisible) shell in this mode where you can inject commands to the server or client. e.g. it can always be christmas in the lobby if you do `sc DA 01 00 00`
- increased the mtu on PSODolphinConfig's tap0 configuration; this seems to make the connection more stable
- fixed some uninitialized memory bugs
- the shell is now event-driven and now uses libevent too; unfortunately this means readline doesn't work anymore (no history and vim-like shortcuts)
- made network command display consistent for input vs. output (the header appears in both cases now)
- fixed bugs in some subcommand handling (the BB logic was being applied to non-BB clients erroneously, causing most item drops not to work at all)
- fixed player tags in the short lobby data struct. unclear if this was actually a problem but it was inconsistent with other servers
- fixed "unused" field in game join command (actually it appears to be disable_udp and should be 1, not 0)
- cleaned up Server abstraction a bit
- rewrote some text functions; asan was complaining about the built-in ones for some reason
- added an optional welcome message

Client.cc

@@ -20,9 +20,9 @@ Client::Client(struct bufferevent* bev, GameVersion version,
     flags(flags_for_version(version, 0)), bev(bev),
     server_behavior(server_behavior), should_disconnect(false),
     play_time_begin(now()), last_recv_time(this->play_time_begin),
-    last_send_time(0), in_information_menu(false), area(0), lobby_id(0),
-    lobby_client_id(0), lobby_arrow_color(0), next_exp_value(0),
-    infinite_hp(false), infinite_tp(false), can_chat(true) {
+    last_send_time(0), area(0), lobby_id(0), lobby_client_id(0),
+    lobby_arrow_color(0), next_exp_value(0), infinite_hp(false),
+    infinite_tp(false), can_chat(true) {
 
   int fd = bufferevent_getfd(this->bev);
   get_socket_addresses(fd, &this->local_addr, &this->remote_addr);
@@ -31,8 +31,6 @@ Client::Client(struct bufferevent* bev, GameVersion version,
 }
 
 bool Client::send(string&& data) {
-  rw_guard g(this->lock, false);
-
   if (!this->bev) {
     return false;
   }