[QAST dumper] include a bit more info
Revert "Merge remote-tracking branch 'origin/spacey'"

This reverts commit 1db6167740f7306a0e3acf04ccb15dfcc27c3dcb, reversing
changes made to c9bc4a25ba2ca57e3642dbe870da31fd1b661322.
Remove a now-unused option.
Remove a redundant load.
Add a way to specify a custom regex lib.

Useful for nqp-jvm while it only has the runtime part of it.
Merge branch 'master' into target-pbc