Update version numbers for Circe 1.2 release.
tracking-next-buffer: Switch to buffer to force mode line update.

This seems to work, and better (more efficient) than the sit-for.
'defcustom circe-default-properties-alist' removed (obsolete)
circe-message-option-functions: docstring clarification
circe.el: correct two docstrings
shorten-join-sans-tail: new util for shorten.el