#6 Release references to unused WPF Window when closing the config window

[Jonathan Camp]

The memory usage of the application domain itself is low, but the unmanaged memory usage from WPF grows to about 50MB after launching the config window, which is currently not available for garbage collection after closing the window. I believe this is because the Application context is holding on to references. This will require memory profiling and probably refactoring the application load.

Acceptance: After closing the configuration window, the memory usage will eventually decrease when GC runs.