test project user credentials
- Instance mutex getter now checks if object is disposed

- moved Instance.Name and Instance.World to Instance.Properties.cs
- fixed parameter order of AvatarPosition from "pitch, yaw" to "yaw, pitch" to be more consistent with other methods and types handling position
- source reorganization
- renamed invalidpassword reason code to invalidlogin

- fixed Login and Enter instance methods not resetting "isPumping" state on exception