Fix for using Gmsh 4.10

Fix for using Gmsh 4.10
Two algorithms from Gmsh 4.10 for generating quad mesh, Packing of Parallelograms and Quasi Structured Quad,
depend on frame/cross-field computations in Gmsh. As such when using these algorithms a class Field is used
(see Field.h in gmsh source). As the class Field also exists in src/SMESHGUI/SMESHGUI_MeshInfo.cxx this cr-
eates an error for displaying the mesh Info.

Hence the Field has been renamed as FieldInfo in src/SMESHGUI/SMESHGUI_MeshInfo.cxx.