* Changed CalcGasLimit to no longer need current block
* Added a gas * price + value on tx validation
* Transactions in the pool are now re-validated once every X

64bit atomic operations are not available on all 32bit platforms.

When worker encounters a gas limit error, subsequent txs should be
ignored from that particular account. This will prevent:

1. Nonce errors been thrown all around
2. The "Known tx" error. Closes #719
3. Repeated contract address. Closes #731

Processing transactions should continue when a transaction throws a gas
limit reached error. Other transactions may actually succeed.

The transaction pool will now some easily be able to pre determine the
validity of a transaction by checking the following:

* Account existst
* gas limit higher than the instrinsic gas
* enough funds to pay upfront costs
* nonce check

Logs are now recorded per transactions instead of tossing them out after
each transaction. This should also fix an issue with
`eth_getFilterLogs` (#629) Also now implemented are the `transactionHash,
blockHash, transactionIndex, logIndex` on logs. Closes #654.

* miner control moved to `admin.miner`
* miner option to set extra data
* block extra now bytes

The uncle rewards were changed in the block processor. This change will
reflect those changes in the miner as well.

* Miners could stall because the worker wasn't aware the miner was done

* In case of uncle mining (e.g. same TS) the miner would stop if all
  threads happened to mine a potential uncle

* Instead of delivering `Work` to the `Worker`, push a complete Block to
  the `Worker` so that each agent can work on their own block.

* WIP missing arguments for submitting new work
* GetWork **done**