v0.1.21 - final(?) alpha release

This server is now running Publ v0.1.21, which I believe will be the final beta version; all of the release blockers have been taken care of. And as a bonus I also implemented the ability to include template fragments, which allows templates' content to change formatting based on the category of the formatted entries. This is particularly useful on Atom feeds, where you might want to have different entry formats for each category. I’m already using it on busybee, to provide full-content feeds in ways that make sense for the different site sections.

I will play with this for a few days and if I’m happy with it I’ll be releasing v0.2.0, which will be the first beta release. In the meantime I’ll also look into packaging up busybee’s templates for other people to use as a starting point, because I know that setting up a new site right now can be incredibly overwhelming!