Pyetherchain

**bugfix**

* fix `python -m pyetherchain` failing with an error (bug)
* lazy load remote information to avoid causing too many requests (performance)

* switched to python3
* switched to eth-abi for decoding
* code cleanup

* fixed error handling for non-contract accounts

🔥 first release 👍

* etherchain.org api connector
* EtherChain interface class as main entry point to etherchain.org
* interface to explorational features (get blocks, transactions, pending transactions)
* interface to stats and charts
* modes
* interactive
* commandline
* abi based human readable description of historical transactions and the contract creation