Show some common units for reaction rate constants

[schneiderfelipe]

As suggested by G. Caramori, it would be nice to have some different units being shown at the same time for reaction rate constants when doing $ overreact model.k. For this to work, we need to:

• Show a single column in s-1 for unimolecular reactions.
• Show a couple of columns for bimolecular reactions with other units (at least M s-1, cm3 particle-1 s-1, and atm s-1).
• Generalize the above and ensure similar output for termolecular reactions.