[doc] Link material/fracture_model for LIE pcs.

Documentation/ProjectFile/prj/processes/process/HYDRO_MECHANICS_WITH_LIE/fracture_model

+../../../../material/fracture_model
\ No newline at end of file

Documentation/ProjectFile/prj/processes/process/HYDRO_MECHANICS_WITH_LIE/fracture_model/i_fracture_model.md

-Fracture models used in LIE/XFEM solvers.

Documentation/ProjectFile/prj/processes/process/HYDRO_MECHANICS_WITH_LIE/fracture_model/t_type.md

-The fracture model type describing the fracture's opening and closing behaviour.

Documentation/ProjectFile/prj/processes/process/SMALL_DEFORMATION_WITH_LIE/fracture_model

+../../../../material/fracture_model
\ No newline at end of file

Documentation/ProjectFile/prj/processes/process/SMALL_DEFORMATION_WITH_LIE/fracture_model/i_fracture_model.md

-Fracture models used in LIE/XFEM solvers.

Documentation/ProjectFile/prj/processes/process/SMALL_DEFORMATION_WITH_LIE/fracture_model/t_type.md

-The fracture model type describing the fracture's opening and closing behaviour.