Remove all prefixes to modules

youmubot/src/commands/admin/mod.rs

@@ -16,7 +16,6 @@ group!({
     name: "admin",
     options: {
         only_in: "guilds",
-        prefixes: ["admin", "a"],
         description: "Administrative commands for the server.",
     },
     commands: [clean, ban, kick, soft_ban, soft_ban_init],

youmubot/src/commands/fun/mod.rs

@@ -20,7 +20,6 @@ use votes::VOTE_COMMAND;
 group!({
     name: "fun",
     options: {
-        prefixes: ["fun", "f"],
         description: "Random commands",
     },
     commands: [roll, pick, name, vote],