* Tables containing links with a link text were misparsed, because the "|"••• in the wikilink looked like a table field separator. Avoid this ambiguity
by linkifying the data before parsing it as a table.
* Turn on allow_loose_quotes in the table plugin's Text::CSV object,
so that links from wikilinks don't confuse the parser.
* Support for looking in multiple directories for underlay files.•••* Plugins can add new directories to the search path with the add_underlay
function.
* Split out smiley underlay files into a separate underlay, so if the plugin
isn't used, the wiki isn't bloated with all those files.