Add a --debug flag to configure.sh to add the .mdb files to the add-in.

When you `./configure.sh --debug` or `configure.bat --debug`, you can debug the adding in XS by just pressing the big play button.
This switch removes xml comment tags in FSharpBinding.addin.xml, so the list of .mdb files can be managed in FSharpBinding.addin.xml.orig like the list of assemblies are.