impromptu: add or update documentation for commands

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

doc/source/commands.rst

@@ -218,6 +218,11 @@ These commands work in *any* tab.
     /invitations
         Show the pending invitations.
 
+   /impromptu
+        **Usage:** ``/impromptu <jid> [jid ..]``
+
+        Invite specified JIDs into a newly created room.
+
     /activity
         **Usage:** ``/activity [<general> [specific] [comment]]``
 
@@ -472,6 +477,12 @@ Normal Conversation tab commands
         Get the software version of the current interlocutor (usually its
         XMPP client and Operating System).
 
+   /invite
+        **Usage:** ``/invite <jid> [jid ..]``
+
+        Invite specified JIDs, with this contact, into a newly
+        created room.
+
 .. _rostertab-commands:
 
 Contact list tab commands

poezio/core/core.py

@@ -1874,9 +1874,9 @@ class Core:
         self.register_command(
             'impromptu',
             self.command.impromptu,
-            usage='<jid> [<jid> ...]',
-            desc='Invite people into an impromptu room',
-            shortdesc='Invite someone in a room.',
+            usage='<jid> [jid ...]',
+            desc='Invite specified JIDs into a newly created room.',
+            shortdesc='Invite specified JIDs into newly created room.',
             completion=self.completion.impromptu)
         self.register_command(
             'invitations',