* Rakefile: replace deprecated rdoc/gem rake tasks
* Rakefile: replace deprecated rdoc/gem rake tasks

applewiskey/ruby-augeas,hercules-team/ruby-augeas,lutter/ruby-augeas,applewiskey/ruby-augeas,lutter/ruby-augeas,joshuaspence/ruby-augeas,hercules-team/ruby-augeas,joshuaspence/ruby-augeas