for macro: allow alternate :max-tries as meta
First try at parsing, I don't think this will work

Because of things like #"\Qabc\E*". Might try a simpler parser with an
analyzer.
Reviving this idea
The only failures I don't understand
I swear this is progress
Tests are hard to fail now
Upgrade the heck out of test.check
This is impossibly difficult.
WIP: Rethinking character class parsing
Seem to be parsing character classes correctly

Finally.
Better dev errors and another regression case
Slow progress
Make numeric repetition more likely to generate
PartialQE can end with a slash
Flags, more dangling curlies
Another regression check
I'll tell you what this stuff nuts.
More than I ever cared to know
I don't think we needed RangeWithDash anymore
More messing with ampersands