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

When configured with --debug, you can debug the adding in XS by just pressing the 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.
Install .pdb files for windows instead of .mdb files 
Fixes for windows
Debugging works on XS in Windows.
Still some work left to do
Merge branch 'master' into debug_monodevelop
Make add-in debug work on Mac and Windows.

Changing order of locations to look for XS/MD
Small touch-up in read me
Undo changes to .sln
Clearer instructions in readme
Enable debug from MD/XS without 'make install'.

Found out about this here: http://stackoverflow.com/questions/9637994/how-can-i-debug-monodevelop-add-ins-with-monodevelop
This works for the first compile, but XS needs to be restarted after that. I left a comment at the SO answer
Show the --debug option in configure.fsx help
Correct information on --debug  
Merge pull request #426 from rojepp/debug_monodevelop

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