Support for Ubuntu 12.04

[sstoiana]

So far, the only issue that I've seen with the cookbook on Ubuntu 12.04 is that it doesn't specify the correct package names for S3 support:

--- a/chef/cookbooks/artifact/providers/deploy.rb
+++ b/chef/cookbooks/artifact/providers/deploy.rb
@@ -58,7 +58,7 @@ def load_current_resource
     @artifact_location = [group_id, artifact_id, artifact_version, extension].join(':')
   elsif Chef::Artifact.from_s3?(@new_resource.artifact_location)
     unless Chef::Artifact.windows?
-      %W{gcc make libxml2 libxslt libxml2-devel libxslt-devel}.each do |nokogiri_requirement|
+      %W{gcc make libxml2 libxslt1.1 libxml2-dev libxslt1-dev}.each do |nokogiri_requirement|
         package nokogiri_requirement do
           action :nothing
         end.run_action(:install)