Gettext backend for the knowledge base's own translations.

The host sets the locale per request; this module only owns the catalogues under priv/gettext/:

• default — this module's strings (the notes panel, the sidebar tab)
• leaf — the Leaf editor's strings, for the editor inside the notes panel. Leaf looks its strings up in the "leaf" domain of whatever backend it is given, and the panel gives it this one, so a host gets a translated toolbar without adding Leaf's catalogue to its own.

Shipped: Russian (ru) and Estonian (et); English is the source.