Added a basic cache service to handle interations with the underlying cache implementation. Refactored some code to be more robust.

API/Interfaces/ICacheService.cs

@@ -0,0 +1,21 @@
+using API.Entities;
+
+namespace API.Interfaces
+{
+    public interface ICacheService
+    {
+        /// <summary>
+        /// Ensures the cache is created for the given volume and if not, will create it.
+        /// </summary>
+        /// <param name="volumeId"></param>
+        void Ensure(int volumeId);
+
+        bool Cleanup(Volume volume);
+
+        //bool CleanupAll();
+
+        string GetCachePath(int volumeId);
+        
+        
+    }
+}