This update for libsolv, libzypp, zypper fixes the following issues:

libzypp was updated to 17.25.6:

- Rephrase solver problem descriptions (jsc#SLE-8482)
- Adapt to changed gpg2/libgpgme behavior (bsc#1180721)
- Multicurl backend breaks with with unknown filesize (fixes #277)

zypper was updated to 1.14.42:

- Fix source-download commnds help (bsc#1180663)
- man: Recommend to use the --non-interactive global option rather than the command option -y (bsc#1179816)
- Extend apt packagemap (fixes #366)
- --quiet: Fix install summary to write nothing if there's nothing todo (bsc#1180077)

libsolv was updated to 0.7.16;

- do not ask the namespace callback for splitprovides when writing a testcase
- fix add_complex_recommends() selecting conflicted packages in rare cases leading to crashes
- improve choicerule generation so that package updates are prefered in more cases

This update was imported from the SUSE:SLE-15-SP2:Update update project.