add exmaple

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    optitron (0.0.11)
+    optitron (0.1.0)
       callsite (= 0.0.4)
       ruby2ruby (= 1.2.4)
       ruby_parser (>= 2.0)

examples/cli.rb

@@ -0,0 +1,15 @@
+require 'optitron'
+
+class Runner < Optitron::CLI
+  class_opt 'verbose'
+  class_opt 'environment', :in => %w(production stage development test), :default => 'development'
+  class_opt 'volume', :in => 1..10
+
+  desc "Install stuff"
+  opt 'force'
+  def install(file, source = ".")
+    puts "Installing #{file} from #{source.inspect} with params: #{params.inspect}"
+  end
+end
+
+Runner.dispatch