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.

* GetNonce Returns the canonical nonce
* SetNonce Set the managed account's nonce

Add IsOnCurve check to EC unmarshalling in ECIES decryption

Transaction pool will attempt to ignore invalid transactions it had
previously encountered.

Forward and log EC recover err and remove dup pubkey len check

libsecp256k1 #define NDEBUG

Merge branch 'update_bitcoin_secp256k1_lib2' of https://github.com/Gustav-Simonsson/go-ethereum into Gustav-Simonsson-update_bitcoin_secp256k1_lib2

fixed printing circular structures

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