Apostrophe & more poetic numeral tests

[SpecificProtagonist]

I added some test cases where Satriani was non-compliant with the spec.
In particular, the old apostrophesIgnored test didn't check for apostrophes in general, but within poetic numerals, where any non-letter (apart from the first .) are ignored. I instead added other checks where apostrophes have to be ignored even when not in peotic numerals, which in most cases (e.g. Foo' is ok) caused Satriani to fail to parse the test. At the moment, single quotes are very annoying to implement correctly for very little benefit, so changing the spec instead would probably be a good idea.

The poetic literal test now also checks for ignoring non-letters and the possibility of non-ASCII letters (which can hang Satriani if used as the start and fail to parse elsewise).