Add toplevel Rakefile to run tests, generate docs, etc en masse

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7890 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

Rakefile

@@ -0,0 +1,21 @@
+require 'rake'
+
+env = %(PKG_BUILD="#{ENV['PKG_BUILD']}") if ENV['PKG_BUILD']
+
+PROJECTS = %w(actionmailer actionpack activerecord activeresource activesupport)
+
+Dir["#{File.dirname(__FILE__)}/*/lib/*/version.rb"].each do |version_path|
+  require version_path
+end
+
+desc 'Run all tests by default'
+task :default => :test
+
+%w(test docs package pgem release).each do |task_name|
+  desc "Run #{task_name} task for all projects"
+  task task_name do
+    PROJECTS.each do |project|
+      system %(cd #{project} && #{env} rake #{task_name})
+    end
+  end
+end