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/_CommandShowResult.py

@@ -26,6 +26,7 @@ __url__ = "http://www.freecadweb.org"
 
 ## @package CommandShowResult
 #  \ingroup FEM
+#  \brief FreeCAD Command show results for FEM workbench
 
 from FemCommands import FemCommands
 import FreeCADGui

src/Mod/Fem/importCcxDatResults.py

@@ -26,6 +26,7 @@ __url__ = "http://www.freecadweb.org"
 
 ## @package importCcxDatResults
 #  \ingroup FEM
+#  \brief FreeCAD Calculix DAT reader for FEM workbench
 
 import FreeCAD
 import os

src/Mod/Fem/importCcxFrdResults.py

@@ -28,6 +28,7 @@ __url__ = "http://www.freecadweb.org"
 
 ## @package importCcxFrdResults
 #  \ingroup FEM
+#  \brief FreeCAD Calculix FRD Reader for FEM workbench
 
 import FreeCAD
 import os

src/Mod/Fem/importInpMesh.py

@@ -27,6 +27,7 @@ __date__ = "04/08/2016"
 
 ## @package importInpMesh
 #  \ingroup FEM
+#  \brief FreeCAD INP file reader for FEM workbench
 
 import FemMeshTools
 import FreeCAD

src/Mod/Fem/importVTKResults.py

@@ -28,6 +28,7 @@ __url__ = "http://www.freecadweb.org"
 
 ## @package importVTKResults
 #  \ingroup FEM
+#  \brief FreeCAD Result import and export VTK file library
 
 import os
 import FreeCAD

src/Mod/Fem/importZ88Mesh.py

@@ -26,6 +26,7 @@ __url__ = "http://www.freecadweb.org"
 
 ## @package importZ88Mesh
 #  \ingroup FEM
+#  \brief FreeCAD Z88 Mesh reader and writer for FEM workbench
 
 import FreeCAD
 import os

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