Need to combine "schemes/utilities" helper schemes and "phys_utils" function libraries

Currently in CAM-SIMA there are two different ways to calculate common physical or meteorological quantities within the physics suite; either use a scheme from `schemes/utilities`, which can be called directly in the SDF, or use a function from one of the libraries in `phys_utils`, which can be called within a physics scheme itself.

Although they serve two different purposes, this separation results in the same calculations being located in two separate places in the source code, which is not ideal. Thus an improvement would be to "merge" these two methods, for example by calling the `phys_utils` functions within the utilities schemes, which would then move the actual calculations to a single location, and would increase code coverage even with the same number of tests.

Finally, there is also currently an opportunity to simplify the number of total functions that are needed, especially for situations where a function exists to simply calculate the reciprocal of a quantity, and to increase the number of total unit/property tests, which could also be done along with this "merging" cleanup effort.