Move sshpublisher require into the rake tasks that use it so ruby 1.9 and...

Move sshpublisher require into the rake tasks that use it so ruby 1.9 and macruby don't need the rake gem installed

activesupport/Rakefile

 require 'rake/testtask'
 require 'rake/rdoctask'
 require 'rake/gempackagetask'
-require 'rake/contrib/sshpublisher'
 
 require File.join(File.dirname(__FILE__), 'lib', 'active_support', 'version')
 
@@ -65,12 +64,14 @@ end
 
 desc "Publish the beta gem"
 task :pgem => [:package] do
+  require 'rake/contrib/sshpublisher'
   Rake::SshFilePublisher.new("gems.rubyonrails.org", "/u/sites/gems/gems", "pkg", "#{PKG_FILE_NAME}.gem").upload
   `ssh gems.rubyonrails.org '/u/sites/gems/gemupdate.sh'`
 end
 
 desc "Publish the API documentation"
 task :pdoc => [:rdoc] do 
+  require 'rake/contrib/sshpublisher'
   Rake::SshDirPublisher.new("wrath.rubyonrails.org", "public_html/as", "doc").upload
 end