FEM: Doxygen tweeks

Discussion in [FEM subforum](https://forum.freecadweb.org/viewtopic.php?f=18&t=12833&start=40#p158684)
...Calculix FRD Reader doxygen tweek
...Calculix INP Reader doxygen tweek
...Result import and export VTK file library doxygen tweek
...Z88 Mesh reader and writer doxygen tweek
...Z88 Disp Reader doxygen tweek
...Command show result doxygen tweek

src/Mod/Fem/importZ88O2Results.py

@@ -26,6 +26,7 @@ __url__ = "http://www.freecadweb.org"
 
 ## @package importZ88O2Results
 #  \ingroup FEM
+#  \brief FreeCAD Z88 Disp Reader for FEM workbench
 
 import FreeCAD
 import os