hom: recover_bones() works for displacements and pressure
hom: recover_bones() works for displacements and pressure

- computes and saves for several macro-elements

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