PartDesign: Refactor pattern features and gui

- remove StdDirection,StdAxis and StdMirrorPlane properties
- support sketch H_Axis, V_Axis, N_axis as valid references in patterns
- polish reference selection gui (unified for standard axes and custom references)

src/Mod/PartDesign/App/FeatureTransformed.cpp

@@ -71,6 +71,15 @@ App::DocumentObject* Transformed::getSupportObject() const
         return NULL;
 }
 
+App::DocumentObject* Transformed::getSketchObject() const
+{
+    std::vector<DocumentObject*> originals = Originals.getValues();
+    if (!originals.empty() && originals.front()->getTypeId().isDerivedFrom(PartDesign::SketchBased::getClassTypeId()))
+        return (static_cast<PartDesign::SketchBased*>(originals.front()))->getVerifiedSketch();
+    else
+        return NULL;
+}
+
 short Transformed::mustExecute() const
 {
     if (Originals.isTouched())