`dylib` support

[rob9315]

It would be nice to have dylib support for when there is a shared dylib dependency between multiple rust targets, right now this error message is displayed as it ignores dylibs.

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The idea was to compile a shared rust dependency as a dynamic library because compilation artifacts aren't shared when using corrosion in different catkin packages. This however doesn't work as corrosion will refuse to compile the dylib. Using a cdylib is not an acceptable tradeoff as it would require making the library c-ffi-safe which would not be needed with either shared compilation artifacts or a dylib which was compiled with the same compiler as the bin using it.