Added documentation for new functions

man/check_file_extension.Rd

man/generate_as_node_func.Rd

man/generate_as_node_method_content.Rd

man/generate_simple_read_in.Rd

man/get_value_types.Rd

man/guess_structure.Rd

man/node_to_r2ogs6_obj.Rd

man/order_parameters.Rd

man/pick_vtu_file.Rd

man/read_in.Rd

man/read_in_curves.Rd

man/read_in_gml.Rd

man/read_in_linear_solvers.Rd

man/read_in_media.Rd

man/read_in_nonlinear_solvers.Rd

man/read_in_parameters.Rd

man/read_in_points.Rd

man/read_in_polylines.Rd

man/read_in_prj.Rd

man/read_in_process_variables.Rd