Add more xmldoc

osu.Game/Database/ICanAcceptFiles.cs

@@ -1,9 +1,19 @@
 namespace osu.Game.Database
 {
+    /// <summary>
+    /// A class which can accept files for importing.
+    /// </summary>
     public interface ICanAcceptFiles
     {
+        /// <summary>
+        /// Import the specified paths.
+        /// </summary>
+        /// <param name="paths">The files which should be imported.</param>
         void Import(params string[] paths);
 
+        /// <summary>
+        /// An array of accepted file extensions (in the standard format of ".abc").
+        /// </summary>
         string[] HandledExtensions { get; }
     }
 }