Fixes #399

Florian Münchbach authored 6 years ago and Florian Münchbach committed 6 years ago

This commit contains all changes starting with the first integration of
the plugin into the gajim_1.1 branch (76dabe2e) until the current plugin
version V3 (42b9aeb8).
The manifest.ini is updated for compatibility with upcoming Gajim
versions.