documented 'jekyll_date_chart', 'jekyll_image_encode' and 'jekyll_quick_man' in the plugins list
Change day example to a one-digit
Merge pull request #1405 from GSI/master

documented new gem 'jekyll_image_encode' in the plugins list
Update history to reflect merge of #1405
Downgrade Listen to 1.3.x

This is so that we can be Ruby 1.8.x compatible.
Merge pull request #1663 from penibelst/emphasize-date-filters

Change day example to emphasize the leading zero
Update history to reflect merge of #1663