Implemented the BundleServicing protocol in the library target.

Library/Sources/Protocols/BundleServicing.swift

@@ -0,0 +1,9 @@
+import Foundation
+
+public protocol BundleServicing {
+
+    // MARK: Functions
+    
+    func url(forResource name: String?, withExtension ext: String?, subdirectory subpath: String?) -> URL?
+    
+}