removed accidental add of the built gem, rearranged build order in Rakefile

Author: Christopher Brown

Rakefile

@@ -1,4 +1,4 @@
-gems = %w[chef chef-server]
+gems = %w[chef chefserverslice chef-server]
 
 desc "Build the chef gems"
 task :gem do
@@ -29,4 +29,4 @@ namespace :dev do
     end
     Dir.chdir("example-repository") { sh("rake install") }
   end
-end
+end