increase required precision in examples/acoustics/acoustics3d.py
increase required precision in examples/acoustics/acoustics3d.py

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