Adding platforms to swift 5 specific package manifest, but keeping the one without it to retain spm compatibility for xcode 10.

Author: jeffctown

Package.swift

@@ -1,11 +1,8 @@
-// swift-tools-version:5.1
+// swift-tools-version:4.0
 import PackageDescription
 
 let package = Package(
     name: "OHHTTPStubs",
-    platforms: [
-        .macOS(.v10_10), .iOS(.v8), .watchOS(.v2), .tvOS(.v9)
-    ],
     products: [
         .library(
             name: "OHHTTPStubs",

Package@swift-5.swift

@@ -0,0 +1,41 @@
+// swift-tools-version:5.0
+import PackageDescription
+
+let package = Package(
+    name: "OHHTTPStubs",
+    platforms: [
+        .macOS(.v10_10), .iOS(.v8), .watchOS(.v2), .tvOS(.v9)
+    ],
+    products: [
+        .library(
+            name: "OHHTTPStubs",
+            targets: [
+                "OHHTTPStubs",
+            ]
+        ),
+        .library(
+            name: "OHHTTPStubsSwift",
+            targets: [
+                "OHHTTPStubs",
+                "OHHTTPStubsSwift"
+            ]
+        )
+    ],
+    dependencies: [
+    ],
+    targets: [
+        .target(
+            name: "OHHTTPStubs",
+            dependencies: []),
+        .testTarget(
+            name: "OHHTTPStubsTests",
+            dependencies: ["OHHTTPStubs"]),
+        .target(
+            name: "OHHTTPStubsSwift",
+            dependencies: ["OHHTTPStubs"]),
+        .testTarget(
+            name: "OHHTTPStubsSwiftTests",
+            dependencies: ["OHHTTPStubsSwift", "OHHTTPStubs"]
+        )
+    ]
+)