* Revert previous revert (9ba23946d1)
* Correctly fall back to Modern if tagless binding projects
* Rework binding tests to cover all supported configurations
* Add XM_FORCE_MSBUILD env variable for mmp/msbuild mac tests for easy local checking
- Fixes https://github.com/xamarin/xamarin-macios/issues/3608
- Refactor and clean up msbuild to be more consistent between binding and "normal" workloads
- Comment on the inconsistencies that are too large to fix in one PR
- Write some actual tests for binding projects to detect regressions
- Due to lack of redirect support these tests are only xbuild current, but I ran tests with msbuild to validate locally
* [tests] Build the native test library for macOS and create a binding project for it.
Also add the new binding project to the xammac and link all XM test projects,
which allows us to stop excluding tests that require the native library and
the corresponding bindings.
* [tests] Include more tests in xammac_tests.
* [tests] Correctly ignore the ObjC exception tests in release mode.