* Problem: acceptance-test suite is not documented
Solution: add README.md in the root of the acceptance tests, unify
`Makefile` and commands, remove more cached files when `make clean` is
ran.
* Problem: documentation does not mention Makefile
Solution: update docs with our new and shiny commands
* Problem: it's difficult to run/test/compile docs
Solution: we already have a nice Makefile, but it's outdated. The idea
is to revamp it and make it easy to use.
* Problem: Makefile is not documented
Solution: Add basic instructions on how to use it in the main README.md
* Problem: can't connect to localhost:9984
Solution: make docker expose 9984 by default, so everyone can connect to
localhost:9984.
* Problem: make clean is TMI
Solution: add `@` to remove commands so we don't output all the details
about the cleaning
* Problem: make clean is too shy
Solution: print a message saying that cleaning went well.
* Remove testing for rethinkdb, mongodb, and Py3.5
* Add first tests
* Add validation
* Add command to start the ABCI Server
* Reuse existing MongoDB Connection class
* Use DuplicateTransaction
* Test only tendermint
* Update travis scripts
* Fix pep8 errors
* Update Makefile