Fix SMESHGUI_Measurements.cxx
In "Build Compound Mesh", set "Merge coincident nodes and elements" ON by default
after reflection about a question on the Forum http://www.salome-platform.org/forum/forum_11/866636535
Change SMESHGUI_BuildCompoundDlg.cxx
+ Pre-open MED file to speed-up reading/writing (following 22349)
+ Clock-cursor in Display Entity dlg
+ In Filter dlg, do not perform filtering if it's not needed
+ In Group dlg, store a user-given name of a new group
+ Clock-cursor after hypothesis modif as mesh clearing can be long
+ Treat selected object right at opening of Measure dlgs
+ Allow removal of elements in a not shown mesh
+ Make filter work on a not shown mesh
+ Don't leave orphan nodes at RemoveGroupWithContents
+ Avoid crash when exporting a group + fields