add paramifier "recent:N" to show N most recently modified tiddlers on startup

[EricShulman]

as described in the summary, this paramifier makes it easy to open a document and immediately view the most recently changed tiddlers.

config.paramifiers.recent= {
	onstart: function(v) {
		var titles=[];
		var tids=store.getTiddlers("modified","excludeLists").reverse();
		for (var t=0; t<v && t<tids.length; t++)
			titles.push(tids[t].title);
		story.displayTiddlers(null,titles); 
	}
};

[MartinBudden]

Fixed in changeset:5889