TextEditor: add action to paste without autoFormat

Fixes: QTCREATORBUG-20887
Change-Id: Iedc6b584c9c1cc48804025653d0749e054a406f8
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/texteditor/texteditor.h

@@ -366,6 +366,7 @@ public:
     void setExtraEncodingSettings(const TextEditor::ExtraEncodingSettings &);
 
     void circularPaste();
+    void pasteWithoutFormat();
     void switchUtf8bom();
 
     void zoomF(float delta);