[Commands] Cleanup #guild Command (#2693)

# Commands
- Adds `#guild search [Search Criteria]` sub command.

# Notes
- Allows operators to search for a guild instead of listing all guilds at once.
- Adds a method for sending guild sub commands to make code drier.

zone/command.h

@@ -33,6 +33,7 @@ std::map<std::string, std::string> GetModifyNPCStatMap();
 std::string GetModifyNPCStatDescription(std::string stat);
 void SendNPCEditSubCommands(Client *c);
 void SendRuleSubCommands(Client *c);
+void SendGuildSubCommands(Client *c);
 
 // Commands
 void command_acceptrules(Client *c, const Seperator *sep);