EIPs 155, 160, 161 (#2976)

* The front-end for each hard-fork, also EIP-160.

* Address EIP161 a/c

* Include EIP-161b

* EIP-161 part d.

* Fix test build.

* Fix one test, add another.

* Fix use of bloom & renaming.

* Initial groundwork for EIP-155

* Fix minor bug.

* Fix all tests finally.

* Rest of EIP-155.

* Add tests for EIP-155 algorithm.

Update transaction tests validation.

* Minor reformat.

* Address grumbles.

* Remove unused code.

* Fix SUICIDE gas mechanism and add consensus tests.

* Remove commented code.

* Set Frontier hardfork block number

* Fix warning.

* Transaction tests,

ethcore/src/json_tests/executive.rs

@@ -92,10 +92,18 @@ impl<'a, T, V> Ext for TestExt<'a, T, V> where T: Tracer, V: VMTracer {
 		self.ext.exists(address)
 	}
 
+	fn exists_and_not_null(&self, address: &Address) -> bool {
+		self.ext.exists_and_not_null(address)
+	}
+
 	fn balance(&self, address: &Address) -> U256 {
 		self.ext.balance(address)
 	}
 
+	fn origin_balance(&self) -> U256 {
+		self.ext.origin_balance()
+	}
+
 	fn blockhash(&self, number: &U256) -> H256 {
 		self.ext.blockhash(number)
 	}