Fix a possible problem in MC test: Modify textCSV_GUI.py
Modify opinion_model_OO.py:
Merge branch 'HEAD' of https://godisreal@git.code.sf.net/p/socialnetwork-abs/git
Modify opinion_model.py for showing matrixWPk:
Add new examples for triad test.
Add new examples for periodicity test in the repo.
Record data of convergence into a text file.
Add opinion_model_OO.py in the program and adjust textCSV_GUI.py accordingly.