* gas price distribution + median + tests
* put histogram in util
* use the util histogram
* remove the default gas price implementation
* histogram rpc
* fix empty corpus
* Add JS ethcore_gasPriceHistogram
* Fix typo (s/types/type/) & subsequent failing test
* Fix return type & formatting
* bucketBounds
* Add jsapi e2e test verification
* add auto-args deserialization for RPC
* make block param member public
* change BlockParam to a more generic Trailing<T> mechanism
* define work type
* build_rpc_trait macro, implement eth protocol
* fix up tests
* move eth_filter API to new macro
* Async RPC
* Limiting number of transactions in queue
* Fixing tests
* Bumping serde and jsonrpc-core
* serde updated to 0.8
* fixed failing tests
* Bumping ipc server
* Fixing API for endpoints
* Experimenting with tests without --release mode