[src][script] Enhancement of stbtel (local refinement) and fix bug in execution Python script for long string of filepath

Stbtel local refinement :

• changing original stbtel algorithm to detect polygon inner nodes by the inpoly bief function ;
• adding to stbtel_refine (and to converter.py refinement) an option to do a local refinement by using a GIS file containing (only) one polygon

Python execution fix for long filepath :

• TelemacCas class has been modified (and existing method - contains_multiple_line - has been fixed) to handle long filepath on multiple lines (without mistake with commentary lines). It is based on some assumptions (number of "'", commentary line begins by "/", etc.). It looks robust (on Telemac-Mascaret exception) but it may remain some exceptions.

(this branch should correct the problem of long pathfile in Q4TS @jean-marie.kerloch)