updated dw_volume_lvf to accept a constant scalar force
updated dw_volume_lvf to accept a constant scalar force

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