Add spec & help rules to Rakefile.

Rakefile

@@ -1 +1,26 @@
-require "bundler/gem_tasks"
+
+require 'rake'
+require 'rake/testtask'
+
+Rake::TaskManager.record_task_metadata = true
+
+require 'bundler/gem_tasks'
+
+Rake::TestTask.new do |t|
+  #t.warning = true
+  t.verbose = true
+  t.libs << "spec"
+  t.test_files = FileList['spec/**/*_spec.rb']
+end
+
+# Set default task to list all task
+desc 'Default task (build)'
+task :default do
+  puts 'Usage : rake <taskname>'
+  puts ''
+
+  Rake::application.options.show_tasks = :tasks  # this solves sidewaysmilk problem
+  Rake::application.options.show_task_pattern = //
+  Rake::application.display_tasks_and_comments
+end
+