Newer Test::More lazy-loads more stuff (overload.pm in this case)

Make the 'undefer' dummy test do more work

(cherry pick of 77cc50d1)
(travis) Install older DBD::SQLite on perl < 5.8.4, I fucked up on testing

Related RT: https://rt.cpan.org/Ticket/Display.html?id=99747
ribasushi--

(cherry pick of 21b3c791)
Fix incorrect collapser source being generated due to unicode collapse points

I am not sure how nobody but abraxxa ran into this - the missing escapes have
been used by a ton of people for over a year. In any case the issue is real,
and fixed by trivial {}-escaping.

Add an extra stresstest envvar to make sure this does not regress in the
future (the envvar will be picked up and set by POISON_ENV on travis)

(cherry pick of 2fdeef65)
Fix idiocy that snuck in bdbd2ae8a - I only want fatal undefs

Not sure what I was thinking. In either case - remove the unsafe code, and
annotate the remaining uses of FATAL => 'all'

(cherry pick of 9f7d5590)
Bump Moo dependency

(cherry pick of abc3b8e9c)
Fix endless loop on BareSourcelessResultClass->throw_exception(...)

There is a better fix for this in the pipes, but this will do for now

(cherry pick of 4f52479b)