In preparation for search functionality, added a new function that looks for newer messages when the message pane is scrolled to the bottom. This would be the case if any new messages have arrived since it was last loaded, or if we were viewing a search result from long ago, where the most-recent message displayed would be far from the most recent message in the DB...
Worked around an annoying bug in my core.
Derp :(
Bye-bye magic numbers!
Buffer-searching is now kinda-almost functional! Albeit with much code duplication...