Added support for copying Content projects correctly.

Summary: This adds support for automatically and correctly copying the compiled content folder from Tychaia.Content (and in future, other content projects as well) as part of the C# project that actually uses them.  Unlike XNA which has a dedicated content project type, this updates the project generator to use "Copy on Build" with links to the files so that they get copied across correctly when any project requiring them is built.

Test Plan: Delete any existing `Tychaia\bin` folder that you might have.  Regenerate the projects and then build.  The Tychaia game should build and run from MonoDevelop without files having to be manually copied or any other reconfiguration.

Reviewers: Sabre070

Reviewed By: Sabre070

Maniphest Tasks: T16, T7, T33

Differential Revision: http://code.redpointsoftware.com.au/D19