Clean up and add more Encodable tests
Add writeEnumeratedAPTag
Add doctests.hs

This will be used to run examples in haddock as tests.
Add instances of Eq and Show to Writer

Will be useful for tests.
Implement writeEnumeratedAP
Add test suite for doctests
Add docs target to Makefile
Implement bacnetEncode for Enumerated
Add a haddock property
Add Monoid property tests to WriterSpec
Add a lot of docs to Reader.Core

Add documentation and haddock properties to Reader.Core. Clean up
imports as well.
Add round trip tests for Enumerated
Add documentation and haddock props

Add some props to Writer and some documentation.