MSVC 2008 Projects: Use Custom Build Rules

...for all of the copying of the pre-configured headers for Cogl.  This
makes it much easier for people using the projects for building Cogl to
clean up files that are "generated", and this commit is the last bit for
it.  Also clean up the property sheets as a result.

Also fix the Cogl project that it does indeed look for headers in
cogl/deprecated, so that the build is fixed.

Similar updates to the Visual Studio 2010 Projects will follow.