MOVED: Document the removal of obsoleted port

- devel/rubygem-chef-provisioning
- devel/rubygem-grit
- graphics/rubygem-goocanvas
- sysutils/rubygem-chef15
- sysutils/rubygem-chef-config15
- sysutils/rubygem-chef-dk
- sysutils/rubygem-chef-utils15
- sysutils/rubygem-ohai15
- www/rubygem-kensa