Small typo fix.

releaseses -> releases
Dist.ini - Bump Plack dependency to newest release
WWW::DuckDuckGo requirement.
Added duckpan.js to share dir
Server.pm - Don't request duckpan.js from DuckDuckGo
Server.pm - add duckpan.js back to list so it gets copied from dist_dir
Documentation modified to create sections.