* add a simple test for is_push so that every small utility has a corresponding unit test
* split evm/factory.rs into two files as the TODO suggests
* style fixes according to review comments
* Spliting gasometer out of interpreter
* Choosing right gas calculations implementation based on supplied gas
* Moving verification out of gasometer
* MemGasCost benchmark.
Conflicts:
ethcore/src/evm/benches/mod.rs
* Some simple benchmarks
* Benchmark for simple loop
* Calculating gas_for_memory only when it's actually needed
* Removing superfluous newline [ci skip]
* 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.
