FEM: code formating, make all python module start the same way

- module info
- doxygen documentation
- imports
- code

src/Mod/Fem/_CommandShellThickness.py

@@ -29,10 +29,8 @@ __url__ = "http://www.freecadweb.org"
 
 import FreeCAD
 from FemCommands import FemCommands
-
-if FreeCAD.GuiUp:
-    import FreeCADGui
-    from PySide import QtCore
+import FreeCADGui
+from PySide import QtCore
 
 
 class _CommandShellThickness(FemCommands):