Fixed #10: Avoid "optional" to override code

Move convert the span tag into a class optional
Fixes #13: Add PATCH and OPTION method

Remove HTTP method which is not legit
Fixes #8: Open diff mode in inline on small device
issue #11: Rename bool into boolean
Use integer instead of generic number in validator
Fixes #11: Adding Integer type
Merge branch 'feature/#11' into develop
Issue #12: Add constraints keyword

- Add valildators for common values (min, max...)
- Implement factories
Issue #12: implement constraints on multi-versions
Issue #12: Displaying constraints in rendered doc
Issue #12: Update documentation
Issue #12: Remove minProperties and maxProperties

Useless in apiDoc because, we don't have additionalProperties on objets
Merge branch 'feature/#12' into develop
Fix code indentation
Fix authentification vs authentication
Remove TODO from readme and doc.

Replace by github's issues
Revert default configuration
Change version in setup and documentation
Add informations in setup.py
Set version as a module variable