Use Rsync instead of CP for copying generated source files

[andrewdmontgomery]

Closes #

Description

This does a few things:

• ~Reorganize the Docc documentation to make a home for "Models" documentation~
• ~Update the make generate command so that it copies the documentation to the proper place~
• Update the make generate command to use rsync instead of cp

Rsync instead of CP

If we ever remove (or rename) a model, the cp command will copy the new source file. But it will leave the old source file in place. This rsync command will --delete any files in the destination that are not present in the source.

Testing Steps

• [ ] CI should be 🟢
• Go to the openapi-generator/generated/OpenAPIClient/Classes folder and remove one file:
  • Manually run the rsync command from the Makefile (don't run make generate since that will replace the file you just deleted)
  • [ ] Verify that the file you deleted above is now also missing from Sources/Gravatar/OpenAPI/Generated folder
• [ ] ~Documentation should include a "Models" section~
• [ ] ~The "Articles" section should still be shown at the top of the documentation~

[andrewdmontgomery]

Technically, since we commit the model files, we do generate documentation for those types. See Profile as an example.

Goodness. I must have been tired at the end of the week when I went looking for those models. You are totally right.

My guess is that these generated docs are useful when the generated files are not committed in source control.

Absolutely. I'll remove all that extra stuff.

Update the make generate command to use rsync instead of cp Totally let's do this 🎉

And yep, I'll make this PR just this.

[andrewdmontgomery]

@etoledom I changed the name of this PR to reflect the more limited scope.

[etoledom]

I've just updated from trunk to make this PR mergable