Look for RLBotServer in cwd or %localappdata% if not specified

[NicEastvillage]

• The MatchManager now takes the exact path to the RLBotServer executable, but a find_file helper method is available to recursively look in sub directories
• If a path to the RLBotServer is not provided, the MatchManager will try to find it in the current working directory.
  • If the server is not in cwd, and OS is Windows, it will then look in %localappdata% where the launcher is typically installed.

This is a breaking change for anyone using the current auto-find and launch server methods.

[VirxEC]

LGTM 👍