1. ExtrusionCut: Apply Sketch button(in tool bar) should be applyed only to the sketc...

1. ExtrusionCut: Apply Sketch button(in tool bar) should be applyed only to the sketch. Extrusion should not be committed [XGUI_OperationMgr::commitAllOperations()].

2. Issue #604 Creation of an unexpected line in the Sketcher
a) using canUndo to check whether the sketch can be applyed
b) undo/redo -> update the Apply button state also.