added sfepy/fem/probes.py - FE data probes
added sfepy/fem/probes.py - FE data probes

- added Probe, LineProbe classes - initial version

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