Add support for Python 3.4, pypy3, use travis_retry

http://blog.travis-ci.com/2013-05-20-network-timeouts-build-retries/
Convert readme from markdown to rst for PyPI
Use ABCs instead of list/dict

see https://github.com/stefankoegl/python-json-patch/issues/33
bump version to 1.5
Fix contains unexpected false return
bump version to 1.6
Merge pull request #1 from stefankoegl/master

merged latest from Stefan