8.0 wmsqtyavailprec jco

We want a consistent use of rounding and precision of the product quantities.  The rounding is done according to the rounding of the default product UoM.  Behind the scenes we always convert the quantity of the moves and pack operations to the quantity in default UoM and apply its rounding there before doing any further operations.  Float_compare are done everywhere in stock operations.  @odony 
It is not with UoM, but it is important to have the correct quants after migration.  It is important when a positive quant which came from a negative quant resolves a negative quant.  This one will have a positive quant which needs to refer to the first negative quant.