Fablo init and select which chaincode to init

[dzikowski]

Probably this is a good case to use Yeoman (prompt for chaincode language or forward to dedicated generator). Proposed API:

./fabrica init => prompt
./fabrica init java => create sample Java chaincode
./fabrica init node => create sample Node chaincode
./fabrica init go => create sample Go chaincode
./fabrica init config (?) => no chaincode, config only