repair and streamline VS 2008 projects
MzCOM: avoid the ATL framework

Building MzCOM without ATL means that Visual Studio Express --- or
other free compilers, in principle --- can build MzCOM. It also cleans
up and simplifies the build.

The non-ATL implementation is based on "Com in Plain C" by
Jeff Glatt, and uses a lot of his code (with instructive
comments intact).