Release 3.13.2
Post-release version bump to 3.13.3
build: remove icons

They're unused, they're installed in the wrong icon theme (gnome
was renamed to Adwaita), and the designers don't want them.
build: remove historical baggage

If you want a ChangeLog, use git. It's right there.
build: fix reconfiguration after changelog removal

By telling automake to shut up.

(And remove other changelogs too)