Add an ENUM implementation
Add an ENUM implementation

Several ENUM like classes were defined throughout the code. Now
these have been consolidated into a single implementation which
should be compatible with all PY versions.

Signed-off-by: Kevin Conway <3473c1f185ca03eadc40ad288d84425b54fd7d57@gmail.com>

kevinconway/pycc,kevinconway/pycc