Introduce UncheckedTransaction & test.

substrate/wasm-runtime/polkadot/src/runtime/timestamp.rs

@@ -1,9 +1,10 @@
 use primitives::Timestamp;
+use storage::Storage;
 
 pub fn timestamp() -> Timestamp {
-	unimplemented!()
+	Storage::into(b"tim\0val")
 }
 
-pub fn set_timestamp(_now: Timestamp) {
-	unimplemented!()
+pub fn set_timestamp(now: Timestamp) {
+	now.store(b"tim\0val")
 }