Lua: Hook PlayerMsg to code

Summary

This MR fixes the PlayerMsg Lua hook so that it is hooked to the relevant code that receives messages (XD_SAY packet).

LUA_HookPlayerMsg had its mute parameter removed - no relevant variable exists in the original function it hooks from, so it seemed vestigial.

Testing

Demonstration screenshot:

Testing environment: ringracers_hookPlayerMsgToCode.exe -console -skipintro -server -warp RR_TESTRUN +addfile chathook.lua.

I used a Lua script, chathook.lua, that tests the PlayerMsg hook, printing all its variables. If the player says mute in a message, their message gets muted (the hook will return true) and print that this happened.

sayteam is untested, because Ring Racers does not come with any team gamemodes by default. I have no reason to think it would not work, though.

Changelog

• Lua: fixed PlayerMsg not being hooked up to code.