Clean up METUtilities

Some of the code in the METUtilities package has organically become rather confusing and difficult to deal with over the years. This MR attempts to improve the situation by removing some obsolete material and improving the readability of the rest. Much of this is style improvements. There should be no functionality changes for anyone who is doing anything remotely up-to-date to the best of my knowledge.

Tagging @bhodkins, @stapiaar, @gotero for their awareness, and @khoo who might want to give it a look.