[TD] DrawView*: remove unused includes - part 1

- also sort includes
- also additions to precompiled header

src/Mod/TechDraw/App/DrawViewClipPyImp.cpp

@@ -27,12 +27,12 @@
 
 #include "DrawViewClip.h"
 #include "DrawView.h"
-
 // inclusion of the generated files
 #include <Mod/TechDraw/App/DrawViewPy.h>
 #include <Mod/TechDraw/App/DrawViewClipPy.h>
 #include <Mod/TechDraw/App/DrawViewClipPy.cpp>
 
+
 using namespace TechDraw;
 
 // returns a string which represents the object e.g. when printed in python