use argparse instead of optparse in examples/diffusion/laplace_shifted_periodic.py
use argparse instead of optparse in examples/diffusion/laplace_shifted_periodic.py

BubuLK/sfepy,rc/sfepy,lokik/sfepy,BubuLK/sfepy,vlukes/sfepy,sfepy/sfepy,vlukes/sfepy,rc/sfepy,lokik/sfepy,BubuLK/sfepy,rc/sfepy,lokik/sfepy,sfepy/sfepy,vlukes/sfepy,sfepy/sfepy,lokik/sfepy