Minor changes, fixes and preparation

> Fixed memory clogging caused by absence of finalization suppression on
disposal;
> Wrapped some attributes and function calls in conditionals for future
use;
> All instances of Stream.Close have been renamed to Stream.Dispose;
> Removed struct mapping utility class file - it is no longer needed.

Making preparations for .NET 3.5 and Windows Store compatibility.
RMI may not be supported on those... I'll try looking into a brute-ish
way of including it.