* created ABCI_RPC class to seperate RPC interaction from the other ABCI interactions
* renamed validation.py to validator.py
* simplified planetmint/__init__.py
* moved methods used by testing to tests/utils.py
* making planetmint/__init__.py lean
* moved ProcessGroup object to tests as it is only used there
* reintegrated disabled tests
Signed-off-by: Jürgen Eckel <juergen@riddleandcode.com>