extensions: improve the consistency of synopses Trying as much as possible to consistently: - use a present tense predicate followed by a direct object - verb referring directly to the functionality provided (ie. not "add command that does this" but simple "do that") - keep simple and to the point, leaving details for the long help (width is tight, possibly even more so for translations) Thanks to timeless, Martin Geisler, Rafael Villar Burke, Dan Villiom Podlaski Christiansen and others for the helpful suggestions.