Add im7 core GetDelegates() and GetFeatures()

[coderkun]

ImageMagick provides a function to list all registered delegates and a second function to list built-in features. Both are very useful for applications to know the capabilities of ImageMagick and to verify an ImageMagick installation.

This Pull Request adds the function GetDelegates() which returns the output of GetMagickDelegates() and the function GetFeatures() which returns the output of GetMagickFeatures().

[coderkun]

@justinfx the tests are failing on Linux but it does not seem related to the changes of the Pull Request. Is there anything that I need to do or is the pipeline not working correctlyb

[justinfx]

It's a limitation of github actions not being able to use the same env variables in your fork that are set up in the main repo. So the pipeline can pass until it is running on a branch in the main repo. Sucks, but doesn't seem to be another way.

[coderkun]

Thanks for merging @justinfx but it looks like the fixup commit did not get squashed into the original commit. Do you want to fix that?

[justinfx]

It's not a big deal. Already merged at this point. If it were a lot of fixups I would have wanted to squash it. Thanks!