Update README

Convert from ReST to markdown.
Delete README.rst
rename README
Fix pointers to the next doc
Add github's syntaxic coloration for python
Remove unwanted spaces
README is now README.md
Added __getstate__ and __setstate__ to DotedDict and i18nDotedDict. Problems appeared here when pickling mongokit documents due to apparent lack of these functions.
Merge pull request #142 from petersng/master

Added __getstate__ and __setstate__ to DotedDict and i18nDotedDict.
fix tests
fix some tests so they can pass with python 2.6
fix test_to_json_custom_type
clean up some code
Add travis-ci status