* Firt commit.

* First non-functional but correct implementation of BasicAuthority.

Still needs:
- Sealing infrastructure.

* Punch a hole to give miner access to key store.

* Fix test built.

* Basic version of synchronous mining.

This will seal a block whenever a new transaction comes through.
To be made better we need a timer which will wait for one second after the
last block before sealing a new one - better still would be to cooperatively
interleave blocks with other sealing nodes.

* Add tests.

* Fix minor issues from repotting.

* Address grumbles.

* Bumping clippy

* Fixing warnings found by clippy

* traces cli and jsonrpc api

* missing if in docs

* adding traces to modules

* fixed encoding 0u8

* simplified if else stmt

* tracedb core

* more comprehensive tracedb tests

* fixed minor review issues

* addresses filter

* fixed typos

* replace malformed with corrupted

* trace switch

* db key is generic and can be made smaller

* smaller tracedb keys

* tracedb version

* fixed ignored tests

* rename Tracedb -> TraceDB

* fixed typos

* proves

* trace only top level calls to builtins to avoid DDoS attacks

* fixed tracedb config switches

* fix comments fat replaced with trace

* vector-addressing scheme for localized traces

* removed comments

* removed first, redundant 0 from trace address

* updated db.trace method

* additional tests for tracedb.trace()

* Support `pending` block in RPC

* Forward calls from miner to client in case no pending block is available

* removed redundant unwraps

* fixed compilation error, removed warnings

* fixed transaction queue merge conflict

* fixed failing ethminer doc test

* Even more detailed errors for transaction queue

* Small rename

* Removing macros in favour of functions+try!()

* Changing  to wipe-out all transactions from particular sender lower then given nonce.

* Changing given nonce to be client_nonce

* Fixing test_client to support proper nonces when transactions are added to blockchain

* Fixing logic for transactions from new blocks in chain

* spec loading cleanup in progress

* changed engine field in json spec

* refactored engine params

* polishing spec loading refactor

* fixed compiling json tests

* fixed compiling parity

* removed warnings

* removed commented out code

* fixed failing test

* bringing back removed TODO in spec.