[MSPAINT] Realize Masked Skew

- Add CreateMonoBitmap and CopyMonoImage functions to dib.cpp.
- Add bMono parameter to SkewDIB function.
- Add hbmMask parameter to InsertFromHBITMAP function.
- Add ToolsModel::IsSelection.
CORE-18867

base/applications/mspaint/toolsmodel.h

@@ -82,6 +82,8 @@ private:
 public:
     ToolsModel();
     ~ToolsModel();
+
+    BOOL IsSelection() const;
     int GetLineWidth() const;
     void SetLineWidth(int nLineWidth);
     int GetShapeStyle() const;