refactor: expectation always comes first

[shoenig]

This PR introduces breaking changes, where less/greater helpers now
have the expectation come first. This is to be more consistent with
other functions.

Closes #33

[HeCorr]

I'm wondering why this and so many other test packages use this convention of expected, actual where actual, expected is significantly more readable in my opinion ("expect actual to be expected" / if actual == expected).

[shoenig]

Hi @HeCorr it's a good question.

My best guess is the convention was solidified by JUnit a long, long time ago, e.g. assertEquals and nobody wants to break with convention because at this point it's just what folks expect.