[FLASH-USERS] changing units

[Stephen Brian Amsel]

While I've never gotten FLASH to run on my computer, I think the  
change of constants should be automatic. PhysicalConstants_get has  
units as inputs so its outputs are appropriately scaled. As far as  
I've seen, all solvers use that subroutine to get their constants so a  
change of units using that should work for everything. I suspect the  
only way to be absolutely sure is to run a simple (conveniently low  
runtime) problem with two sets of units, convert the output of one  
yourself, and see if everything matches.