[zathura/f19] (6 commits) ...fix summary, add runtime warning about missing plugin

[François Cami]

Summary of changes:

  43b2286... rewrite description (*)
  705978c... add a zathura-plugins-all subpackage. (*)
  4a51842... rewrite summary as well (*)
  5b25732... backport cf96d52790bc8d05a9e556e33af0b6fec1a4cb0e to displa (*)
  98eaf8d... upstream requested we backport cdece5922982b06e1a86dfb7dfc8 (*)
  7ca42a0... fix summary, add runtime warning about missing plugin

(*) This commit already existed in another branch; no separate mail sent