Mention names of config files on home page

Signed-off-by: Ben Firshman <ben@firshman.co.uk>
Add command line options to the documentation

Signed-off-by: Andrea Grandi <a.grandi@gmail.com>
Merge branch 'andreagrandi-patch-1'

Closes #570.
Merge pull request #533 from bfirsh/mention-configuration-files-on-home-page

Mention names of config files on home page
Update Twitter button URL

I originally left it as orchardup.github.io so the number wouldn't roll
back to 0, but people have been tweeting about fig.sh now.

Signed-off-by: Ben Firshman <ben@firshman.co.uk>
Merge pull request #578 from bfirsh/update-url-in-twitter-button

Update Twitter button URL
support interactive in config yml

Signed-off-by: tsaikd <tsaikd@gmail.com>