srml-contracts: Forbid declaration of float types in contracts (#3234)

* srml-contracts: Forbid remaining uses of float types.

* Bump node runtime impl version.

substrate/node/runtime/src/lib.rs

@@ -80,7 +80,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion {
 	// implementation changes and behavior does not, then leave spec_version as
 	// is and increment impl_version.
 	spec_version: 123,
-	impl_version: 123,
+	impl_version: 124,
 	apis: RUNTIME_API_VERSIONS,
 };