Update Runtime to swift5

Author: Mike Pollard

Package.resolved

@@ -1,4 +1,4 @@
-// swift-tools-version:4.0
+// swift-tools-version:5.0
 import PackageDescription
 
 let package = Package(
@@ -9,7 +9,7 @@ let package = Package(
     ],
 
     dependencies: [
-        .package(url: "https://github.com/wickwirew/Runtime.git", from: "1.1.0"),
+        .package(url: "https://github.com/wickwirew/Runtime.git", from: "2.0.0"),
 
         // ⏱ Promises and reactive-streams in Swift built for high-performance and scalability.
         .package(url: "https://github.com/vapor/core.git", from: "3.0.0"),