Added .gitkeep to directory I intended to check in

but was foiled initially foiled by Git
Extracted Go-specific code into its own file

This is my first step against issue #17
Extracted Python-specific code to its own file

Issue #17
Extracted C++-specific logic into its own file

Also fixed up the "include guards" in the Go and Python files.

Issue #17
Extracted C#-specific logic to its own file

Issue #17
Extracted JavaScript-specific code to its own file

Well, most of it. Issue #17