Part: rename the basic Part 2D and 3D icons

The basic icons for the basic features are renamed,
`Tree_Part` to `Part_3D_object`, `Tree_Part2D` to `Part_2D_object`.

src/Mod/Part/Gui/CommandSimple.cpp

@@ -231,7 +231,7 @@ CmdPartSimpleCopy::CmdPartSimpleCopy()
     sToolTipText  = QT_TR_NOOP("Create a simple non-parametric copy");
     sWhatsThis    = "Part_SimpleCopy";
     sStatusTip    = sToolTipText;
-    sPixmap       = "Tree_Part";
+    sPixmap       = "Part_3D_object";
 }
 
 static void _copyShape(const char *cmdName, bool resolve,bool needElement=false, bool refine=false) {

src/Mod/Part/Gui/Resources/Part.qrc

@@ -83,6 +83,8 @@
         <file>icons/tools/Part_Transformed_Copy.svg</file>
     </qresource>
     <qresource>
+        <file>icons/Part_2D_object.svg</file>
+        <file>icons/Part_3D_object.svg</file>
         <file>icons/Part_BoxSelection.svg</file>
         <file>icons/Part_Export.svg</file>
         <file>icons/Part_Feature.svg</file>
@@ -90,8 +92,6 @@
         <file>icons/Part_Import.svg</file>
         <file>icons/PartWorkbench.svg</file>
         <file>icons/preferences-part_design.svg</file>
-        <file>icons/Tree_Part.svg</file>
-        <file>icons/Tree_Part2D.svg</file>
     </qresource>
     <qresource>
         <file>translations/Part_af.qm</file>

src/Mod/Part/Gui/ViewProvider2DObject.cpp

@@ -83,7 +83,7 @@ ViewProvider2DObjectGrid::ViewProvider2DObjectGrid()
 
     pcRoot->addChild(GridRoot);
 
-    sPixmap = "Tree_Part2D";
+    sPixmap = "Part_2D_object";
 }
 
 ViewProvider2DObjectGrid::~ViewProvider2DObjectGrid()

src/Mod/Part/Gui/ViewProviderExt.cpp

@@ -334,7 +334,7 @@ ViewProviderPartExt::ViewProviderPartExt()
     Lighting.touch();
     DrawStyle.touch();
 
-    sPixmap = "Tree_Part";
+    sPixmap = "Part_3D_object";
     loadParameter();
 }
 

src/Mod/Part/Gui/ViewProviderReference.cpp

@@ -161,7 +161,7 @@ ViewProviderPartReference::ViewProviderPartReference()
     //pShapeHints->ref();
     //Lighting.touch();
 
-    sPixmap = "Tree_Part";
+    sPixmap = "Part_3D_object";
     //loadParameter();
 }
 
@@ -274,7 +274,7 @@ void ViewProviderPartReference::setDisplayMode(const char* ModeName)
 {
     if ( strcmp("Reference",ModeName)==0 )
         setDisplayMaskMode("Reference");
-	
+
     ViewProviderGeometryObject::setDisplayMode( ModeName );
 }