mod_sasl2: Pull user-agent info into sasl_handler for later reference It may be of interest to post-auth things. Putting it on the session was another option considered, but that seemed unnecessary overhead for something that might be rarely used. sasl_handler is cleared after successful authentication.

--% conflicts: mod_bookmarks
module:log("info", "mod_bookmarks has been deprecated, now loading mod_bookmarks2")
module:depends("bookmarks2")