* Groundwork for basic VM tracing.
* RPC endpoint for VM tracing and ser/de types ready.
* Create VMTracer trait.
* Rearchitected VM tracing to reflect existing tracing.
Should more or less work now.
* Integrated VM tracing into JSONRPC.
* Fix ethcore module tests.
* Add tests for VM tracing.
* Fix consensus test code.
* Fix mock tests.
* Added VM trace information for post-execution stuff.
* Fix max-value calls and add "creates" field to getTransaction.
* Tests for VM tracing.
* Don't implement the trait with unimplemented.
* Remove invlaid comment.
* Fix tests.
* use bloomchain crate in blockchain module. remove obsole chainfilter submodule
* update database version to 6.0
* removed redundant line
* simple db migration
* make migration slightly more functional
* bloomchain migration
* migration version is just a single unsigned integer
* updated migration v6
* parity migration
* db migration
* removed hardcoded migration dir
* replace ptr::copy with clone_from_slice, removed potential endianess problem from trace/db.rs
* removed superfluous line
* blockchains log blooms config is not exposed any more