Output expected value on assertion

[jimmy-mcelwain]

In reference to #268.

I am going to make this a draft because I definitely want feedback and expect that I will have to make changes.

The second most recent commit (as of now), 6668a4d0b7b0506ce0427013e578b72d66789bb6 had a function for each assertion, but there was a lot of code duplication. 7c6800716dadd1ed1cbcf4776c40f7e22c07be36 changed that by using more macros.

[jimmy-mcelwain]

I made some small changes that should at least reduce binary size a little bit, nothing big. I'll have to test it more, but I'm mostly looking for design suggestions. I am open to changes, but this has also gotten a bit more complicated than I was hoping and I'm no macro expert.