Initial split of the modules

NadekoBot.Core/Services/IDataCache.cs

@@ -0,0 +1,18 @@
+using StackExchange.Redis;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace NadekoBot.Services
+{
+    public interface IDataCache
+    {
+        ConnectionMultiplexer Redis { get; }
+        Task<(bool Success, byte[] Data)> TryGetImageDataAsync(string key);
+        Task<(bool Success, string Data)> TryGetAnimeDataAsync(string key);
+        Task SetImageDataAsync(string key, byte[] data);
+        Task SetAnimeDataAsync(string link, string data);
+    }
+}