mono-nuget-2.8.7-bp155.2.11

-  update to version 2.8.7

- update to version 2.8.5 for MonoDevelop 5.9

- update to version 2.8.3 for MonoDevelop 5.8 and above
- add fix_xdt_hintpath.patch to fix the build
- add build-minimal.sh as it was removed from the tarball
- add pkgconfig as this contains a .pc file

- initial packaging