[build2] Official build2 Fedora packages

[Matthew Krupcale]

Hello,

First, congratulations on the recent release of build2. I'm happy to
report I've finally gotten build2 into the official Fedora
repositories for Fedora 30[1,2]. Sorry this took so long, but it took
me some time to navigate the review and package submission process as
a new packager.

I also have a few questions / comments since our last correspondence:

1. Have you given any additional thought about using LaTeX CLI
generation to produce PS/PDF documentation output as opposed to the
current html2ps method? I see that there were some commits[3] which
convert some of the problematic characters to ASCII, but unfortunately
this does not make the documents fully ASCII/UTF-8 still. There are a
few NO-BREAK SPACE (U+00A0) and COPYRIGHT SIGN (U+00A9) characters at
the beginning of the PS document, so they're still iso-8859-1 encoded.
What I'm currently doing to fix this on the packaging side is just
using iconv(1) to convert them from iso-8859-1 to utf-8.

2. I noticed that libbutl in a few places[4,5] will invoke exit(3)
directly. I'm not sure if this is intentional, but usually a library
should allow the user executable to decide what to do in the case of
an error, so perhaps in this case it makes sense to just re-throw the
exception and let the executable catch it (or not). This seems to be
what is done in e.g. b_info[6] for a similar use-case.

3. Now that I've finished getting build2 into the official Fedora
repos, and with the work Alex has done on Debian/Ubuntu and
RHEL/CentOS side, do you think it makes sense to do an official
release of ODB at this point? Unless I'm mistaken, this
chicken-and-egg problem was the main reason for delaying the release
of ODB 2.5.0, so with build2 bootstrapped, we should now be able to
build ODB 2.5.0 from the repos.

Best,
Matthew

[1] https://bugzilla.redhat.com/show_bug.cgi?id=1685200
[2] https://bodhi.fedoraproject.org/updates/FEDORA-2019-17d1334a4b
[3] https://git.build2.org/cgit/build2/commit/?id=8ceb809c28f663bb1473722de3c6a24319888e61
[4] https://git.build2.org/cgit/libbutl/tree/libbutl/pager.cxx?id=6bad683716510e148852856417bd8558a7735195#n186
[5] https://git.build2.org/cgit/libbutl/tree/libbutl/process-run.cxx?id=6bad683716510e148852856417bd8558a7735195#n58
[6] https://git.build2.org/cgit/libbutl/tree/libbutl/b.cxx?id=6bad683716510e148852856417bd8558a7735195#n284