Do things more in the order plClient does them, to be compatible with more servers

(specifically MOSS, which has stricter requirements on the order of requests than apparently MOULa or Dirtsand)
Support Server.Auth.G and Server.Game.G settings in server.ini

There is no reason to use nonstandard G values, but some shards (specifically Minkata) do.
Don’t crash when the server sends zero-length SDL files

This shouldn’t happen, but I was chasing a bug that made it happen.
Bump build number to 918
Merge pull request #6 from cwalther/servercompat

Better compatibility with different servers