gnu: Update texlive packages.
* guix/build-system/texlive.scm (%texlive-tag, %texlive-revision): Update to
texlive-2018.2, revision 49435.
* gnu/packages/tex.scm (texlive-dvips, texlive-generic-unicode-data,
texlive-generic-dehyph-exptl, texlive-generic-hyph-utf8, texlive-fontname,
texlive-fonts-cm, texlive-tex-plain, texlive-latex-base,
texlive-latex-graphics, texlive-latex-graphics, texlive-latex-oberdiek,
texlive-latex-tools, texlive-latex-l3kernel, texlive-latex-l3packages,
texlive-latex-fontspec, texlive-latex-amsmath, texlive-latex-amscls,
texlive-latex-babel, texlive-latex-cyrillic, texlive-latex-eqparbox,
texlive-latex-ifplatform, texlive-latex-etoolbox, texlive-latex-galois,
texlive-latex-polyglossia, texlive-tex-texinfo, texlive-latex-changebar,
texlive-latex-fancyhdr, texlive-latex-overpic, texlive-latex-parskip,
texlive-metapost, texlive-latex-ucs, texlive-generic-pdftex,
texlive-latex-media9, texlive-latex-ocgx2, texlive-latex-koma-script,
texlive-generic-listofitems, texlive-bibtex, texlive-context-base): Update
hashes.
(texlive-latex-fontspec)[arguments]: Remove custom build target.
(texlive-latex-dinbrief)[arguments]: Add build phase "fix-encoding-error".
(texlive-latex-xkeyval): New variable.
(texlive-latex-pstool)[source]: Fetch from new location.
[build-system]: Use trivial-build-system.
[arguments]: Write simple builder.
[propagated-inputs]: Add texlive-latex-l3kernel, texlive-latex-tools, and
texlive-latex-xkeyval.
[synopsis]: Fix typo.
d4d9a1ece0