Flow, revolution, Pressure, Localization, Unittests

[Tirael]

Hi!

Added Flow, Revolution, changed Pressure, Unit, UnitConverter, UnitSystem (add Russian and invariant localization).
Add unittests for Flow, Revolution, change unittests for Pressure, UnitConverterTests, UnitValueTests.
All tests passed.

[angularsen]

Thanks George, looks good. Merged.

A few minor things I fixed:

• Missing KFSC case in UnitConverter.TryConvertPressure()
• Variable names in FlowTests and RevolutionTests using "meter"
• .ToString() has changed for all classes (but was not yet pushed so you could not know)

Things I did not fix:

• Missing most imperial units in UnitSystem localization, such as Yard and Foot.

Also, may I propose a change in name for Revolution?

For example AngularSpeed, RotationalSpeed or CyclicFrequency appear as good choices in my opinion. What do you think?

Sources:
http://en.wikipedia.org/wiki/Revolutions_per_minute
http://en.wikipedia.org/wiki/Rotational_speed

[Tirael]

Yes, I agree that the name "Revolution" is wrong. "Rotational Speed" will be more correct.