iOS support in CMake

[cboulay]

A user in the Slack channel indicated that they tried the old unmaintained xcodeproject and that didn't work. I suggested trying the CMake build. They made some progress here but had to hack inside the generated files to fix some settings.

I edited the project.pbxproj and made lslver product-type.library.dynamic and that succeeded although Im not sure thats the right way to do it

there was a bunch of stuff in the build settings under linking that had "x86_64" in the path name so I replaced those with arm64 and it appears to have succeeded building the library I'm trying to test it in a single view iPhone app now