Updated list.hbs which just works

Changed the way the tags are shown, now tags will be shown as `tag1, tag2, tag3` 
Previously there were no comma between tags, they were shown as `tag1 tag2 tag3` which looked weird.
Also in the new ghost release `excerpt words=10` will count 10 characters instead of 10 words. updated that to make atleast a paragraph of words.

Working demo at http://www.subho.me