Adding rate rules for water addition to alkene (reverse of dehydration)

These rate rules are reverse of pri-, sec- and tert- alcohol dehydration
rate. The thermochemistry used to reverse the rate coefficients comes from
butanol mechanism dx.doi.org/10.1016/j.combustflame.2010.06.002

The dehydration rates were measured at NIST using a single pulse shocktube.