Decouple virtual machines (#6184)

* work in progress for splitting vms

* evm working

* Evm -> Vm

* wasm converted

* ethcore working

* test fixes

ethcore/src/json_tests/state.rs

@@ -22,7 +22,7 @@ use spec::Spec;
 use ethjson;
 use ethjson::state::test::ForkSpec;
 use transaction::SignedTransaction;
-use evm::env_info::EnvInfo;
+use vm::EnvInfo;
 
 lazy_static! {
 	pub static ref FRONTIER: Spec = ethereum::new_frontier_test();