Refactoring HOS folder structure (#771)

* Refactoring HOS folder structure

Refactoring HOS folder structure:

- Added some subfolders when needed (Following structure decided in private).
- Added some `Types` folders when needed.
- Little cleanup here and there.
- Add services placeholders for every HOS services (close #766 and #753).

* Remove Types namespaces

Ryujinx.HLE/HOS/Services/Am/AppletAE/IStorageAccessor.cs

@@ -0,0 +1,76 @@
+using System;
+
+namespace Ryujinx.HLE.HOS.Services.Am.AppletAE
+{
+    class IStorageAccessor : IpcService
+    {
+        private IStorage _storage;
+
+        public IStorageAccessor(IStorage storage)
+        {
+            _storage = storage;
+        }
+
+        [Command(0)]
+        // GetSize() -> u64
+        public ResultCode GetSize(ServiceCtx context)
+        {
+            context.ResponseData.Write((long)_storage.Data.Length);
+
+            return ResultCode.Success;
+        }
+
+        [Command(10)]
+        // Write(u64, buffer<bytes, 0x21>)
+        public ResultCode Write(ServiceCtx context)
+        {
+            // TODO: Error conditions.
+            long writePosition = context.RequestData.ReadInt64();
+
+            (long position, long size) = context.Request.GetBufferType0x21();
+
+            if (size > 0)
+            {
+                long maxSize = _storage.Data.Length - writePosition;
+
+                if (size > maxSize)
+                {
+                    size = maxSize;
+                }
+
+                byte[] data = context.Memory.ReadBytes(position, size);
+
+                Buffer.BlockCopy(data, 0, _storage.Data, (int)writePosition, (int)size);
+            }
+
+            return ResultCode.Success;
+        }
+
+        [Command(11)]
+        // Read(u64) -> buffer<bytes, 0x22>
+        public ResultCode Read(ServiceCtx context)
+        {
+            // TODO: Error conditions.
+            long readPosition = context.RequestData.ReadInt64();
+
+            (long position, long size) = context.Request.GetBufferType0x22();
+
+            byte[] data;
+
+            if (_storage.Data.Length > size)
+            {
+                data = new byte[size];
+
+                Buffer.BlockCopy(_storage.Data, 0, data, 0, (int)size);
+            }
+            else
+            {
+                data = _storage.Data;
+            }
+
+            context.Memory.WriteBytes(position, data);
+
+            return ResultCode.Success;
+        }
+    }
+}