Added voice store.

Store/IStore.cs

@@ -0,0 +1,12 @@
+namespace HermesSocketServer.Store
+{
+    public interface IStore<K, V>
+    {
+        V? Get(K key);
+        IEnumerable<V> Get();
+        Task Load();
+        void Remove(K? key);
+        Task Save();
+        bool Set(K? key, V? value);
+    }
+}