Provide types with measures

[panesofglass]

Would be nice to be able to generate types that include units assigned. I imagine this could apply by convention or by explicitly indicating the name of the column containing the unit name, e.g. "m", "m/s", etc. At present, if you want to use types with assigned units, you have to define the measure types and the target types, then map the data from SqlCommandProvider's types into the target types, multiplying each measure value by 1.<m/s>, or whatever the type should be.