Fixes and improvements for modern Nim

[PMunch]

• Changed every occurrence of Nimrod to Nim
• Cleaned up some uses of result, return result, and automatic initialisation
• Improved getMOverNBits to not catch IndexError as that would fail with --panics:on
• Cleaned up some signatures with default values e.g. arg: int = 10 to simply arg = 10
• Cleaned up some calls where arguments where named like call(item = item)
• Removed some comments like "Can be called with method style syntax like " as this is just a language feature
• Combined some let statements into blocks
• Added more tests based on the extra code in the main module
• Switched to camelCase from snake_case (this is a Nim style guide choice, if you would like to keep it snake_case I can change it back)