Cfn-pyplates

- Developer docs, release process (fixes 14)
- Broke tests into their own path, split them out by module
- Using semantic_version instead of verlib
- Linted the crap out of stuff
- No more sphinx warnings!
- Normalized quotes: Single quote for strings, double quotes for docstrings
- Lint expectations outlined in dev docs
- unittest2 is now in tests_require where it belongs (fixes 16)
- Brought in the Mapping tyoe from PR 15 (fixes 17)
- Thanks, aquamatt!

- Fixed a packaging error with v0.2.0
- See v0.2.0 release for changes

- Resource attributes (UpdatePolicy, MetaData, etc) now supported
- .add(child) methods return the added child to support dynamic creation
of the child when .add is called, e.g.: `cft.resources.add(Resource())`

- New MetaData types, see the complete package in the related pull request: https://github.com/seandst/cfn-pyplates/pull/10