Added styling customization options

[technomage]

It would be useful to add a few more styling options to the theme:

1. place the tags list and separator in separate spans and classes to allow added css options for spacing. I find I like it better with more space between the date, the separator and the tags.
2. Add a home.hbs and an introductory content area.

Both of these would still require some editing of the theme, until Apps come out, but would reduce the editing and make merges of changes easier. One Apps are available, then lots of customization can be offered more cleanly (we hope).