Implemented some read functions for existing hfss files

Functions Implemented:
property.py:
get_variables(oProject,oDesign='')
project.py:
get_design(oProject, design_name)
get_top_design_list(oProject)
hycohanz.py: edited to import all functions in the above two files.
Implemented GetFaceIds function in modeler3d.py

modeler3d.py:
get_face_ids(oEditor, body_name)