Improve the C code organization

[Sean Kauffman]

• The R and Python C interface code should be moved to their separate subdirectories

• File sizes in general are too large and should be broken up

  • for example, functions for printing/logging could be moved out into separate files

• Some larger functions should be broken up

  • this is particularly bad among functions with internal state machines

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[Sean Kauffman]

I have started doing this by breaking up the semantics checking code into separate files and by moving everything directly related to the DSL into a subdirectory. The organization can still improve, but this addresses a major problem area.