Make ruby-talk graph on about pages readable

Increase the graph size by a small amount to make
the date labels readable.
Provide locales for Ruby slogan
Use localized Ruby slogan
Remove sitelink to missing security page (tr)
Use an https:// link to avoid pulling data over plain-text.
Added rake to the Gemfile.
Switch site.url back to www.ruby-lang.org
Remove obsolete rake task to update timestamps
Remove obsolete include files for timestamps

The timestamps have been removed from ja/dev and ja/downloads.
added deploy task of production
change directory name
Disable import rake tasks and remove dependencies
Going into production: adapt README

The site has just been launched.
gsub from http://redmine.ruby-lang.org to https://bugs.ruby-lang.org
gsub from http://bugs.ruby-lang.org to https://bugs.ruby-lang.org
Merge pull request #83 from znz/new-redmine-domain

replace link from redmine.ruby-lang.org to bugs.ruby-lang.org
Fix typo in ftp download link (de)
Update translation for footer (de)
Update links to Subversion website
Fix header levels in some news posts