Make solc wrapper solidity v4.0 compatible
Make solc wrapper solidity v4.0 compatible

- Handle the 'fallback' type
- Better handle absence of `inputs`
- Take the newly introduced `payable` attribute into account

shahankhatch/pyethereum,shahankhatch/pyethereum,ethereum/pyethereum,ethereum/pyethereum,karlfloersch/pyethereum,karlfloersch/pyethereum