update examples/linear_elasticity/linear_elastic_iga.py for EBCs by function
update examples/linear_elasticity/linear_elastic_iga.py for EBCs by function

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