added command for displaying foreman version

lib/foreman/cli.rb

@@ -3,6 +3,7 @@ require "foreman/helpers"
 require "foreman/engine"
 require "foreman/engine/cli"
 require "foreman/export"
+require "foreman/version"
 require "shellwords"
 require "yaml"
 require "thor"
@@ -11,6 +12,8 @@ class Foreman::CLI < Thor
 
   include Foreman::Helpers
 
+  map ["-v", "--version"] => :version
+
   class_option :procfile, :type => :string, :aliases => "-f", :desc => "Default: Procfile"
   class_option :root,     :type => :string, :aliases => "-d", :desc => "Default: Procfile directory"
 
@@ -80,6 +83,12 @@ class Foreman::CLI < Thor
     end
   end
 
+  desc "version", "Display Foreman gem version"
+
+  def version
+    puts Foreman::VERSION
+  end
+
   no_tasks do
     def engine
       @engine ||= begin

spec/foreman/cli_spec.rb

@@ -74,4 +74,14 @@ describe "Foreman::CLI", :fakefs do
     end
   end
 
+  describe "version" do
+    it "displays gem version" do
+      foreman("version").chomp.should == Foreman::VERSION
+    end
+
+    it "displays gem version on shortcut command" do
+      foreman("-v").chomp.should == Foreman::VERSION
+    end
+  end
+
 end