Use String#encode instead of deprecated methods
Do not use String#escape
Do not use String#escapeHTML
Remove unused deprecated methods
Drop Ruby 1.8 support
doc: Update
Remove unused files

refs: #55
xmlrpc: Use UTF-8 as wiki encoding
Fix style
plugin incremental search: Use UTF-8
plugin rss-show: Use UTF-8
plugin rss-show: Use meaningful name
plugin trackback: Use UTF-8
plugin auth_typekey: Use UTF-8
util: Remove deprecated methods
Cleanup
remove unused variables
Revert "remove unused variables"

This reverts commit 351bd57e5cea0e41e468ea504e6590cc1b9d7d51.
remove unused variables
added production group