hub.darcs.net :: cbou -> science-constants -> files

The package is open to any scientific constant (and not only in SI units),
so feel free to add new values (or correct existing, if necessary).

TODO/things to consider:

Science.Constants.EV -- constants in electronvolt units
Science.Constants.Planck -- constants in Planck units
Science.Constants.Chemistry -- elements/isotopes' constants
Science.Constants.*.{UnitTyped,Dimensional} wrappers?