catgirl 2.2

This release allows setting fallback nicks, treating all of them
as highlights.  Unknown IRC numeric replies are now written to the
network and channel windows, visible with C--.

The /setname command no longer tab-completes if it is unavailable.
The /nick command with no new nick now reports your current nick.
Topic diffs are now shown on two separate lines.  STATUSMSG messages
are now prefixed with their prefix.

The C-l key now properly redraws the UI in all cases.  Editing by
character now skips non-spacing characters.  Leadings dots are now
sanitized from log path components.  A missing LIST reply topic
parameter no longer causes a crash.  The away reply in a /whois
response no longer depends on nick colouring.

The build instructions for sandman have once again changed.

Thanks to Christian Kellermann and Samanta Navarro for contributions
to this release.