Tweak wording of suppressed warnings message
Terminate early on unrecoverable errors

Technically the document may not be stable in other respects (e.g.,
warnings could change), but it's probably better to get back to the
user quickly with these errors than to keep stabilizing the things
that don't matter as much.
Fix key finding for bibtex warnings that say "in X" multiple times

Previously, if a warning happened to contain the phrase " in
<something>" in addition to " in <key>", latexrun would only try to
match the first <something> as a key.  Fix this by scanning all
phrases of this form.
Sort BibTeX errors
Simplify paths from BibTeX that are in the source directory

This cleans up error messages and also makes dependency information
more portable from one directory to another.
Fix stack matching regexp for long macro expansions

If an error stack includes a macro expansion that's long enough to
trigger eliding, TeX will print "\macroname ..." rather than
"\macroname #1->" (or similar).  Tweak the regexp to handle this case.
Report position on line in error stacks

Previously, latexrun only reported the "before" part of each error
stack line.  Often this was enough, but sometimes the important part
is in the "after" part and this was very confusing (and often required
looking in the log to find the "after" part).  Fix this by reading and
including the "after" part.  Use a ^ marker to indicate where on the
line the error was, which is the more modern convention for this.
Fix exception when using LuaTeX and a fatal error occurs