/usr/share/doc/gromacs/html/dev-manual/ is in gromacs-data 2018.1-1.
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/usr/share/doc/gromacs/html/dev-manual/build-system.html
/usr/share/doc/gromacs/html/dev-manual/commitstyle.html
/usr/share/doc/gromacs/html/dev-manual/documentation-generation.html
/usr/share/doc/gromacs/html/dev-manual/doxygen.html
/usr/share/doc/gromacs/html/dev-manual/error-handling.html
/usr/share/doc/gromacs/html/dev-manual/formatting.html
/usr/share/doc/gromacs/html/dev-manual/gmxtree.html
/usr/share/doc/gromacs/html/dev-manual/includestyle.html
/usr/share/doc/gromacs/html/dev-manual/index.html
/usr/share/doc/gromacs/html/dev-manual/jenkins.html
/usr/share/doc/gromacs/html/dev-manual/language-features.html
/usr/share/doc/gromacs/html/dev-manual/naming.html
/usr/share/doc/gromacs/html/dev-manual/overview.html
/usr/share/doc/gromacs/html/dev-manual/releng/
/usr/share/doc/gromacs/html/dev-manual/releng/index.html
/usr/share/doc/gromacs/html/dev-manual/releng/jenkins-howto.html
/usr/share/doc/gromacs/html/dev-manual/releng/jenkins-ui.html
/usr/share/doc/gromacs/html/dev-manual/relocatable-binaries.html
/usr/share/doc/gromacs/html/dev-manual/reportstyle.html
/usr/share/doc/gromacs/html/dev-manual/style.html
/usr/share/doc/gromacs/html/dev-manual/testutils.html
/usr/share/doc/gromacs/html/dev-manual/tools.html
/usr/share/doc/gromacs/html/dev-manual/uncrustify.html