Added 'download latest CSV export' button and changed the file zip to use rubyzip rather than making a system call to the zip command.
Merge branch 'rails3' of github.com:myGrid/biocatalogue into rails3

# By Aleksandra Nenadic
# Via Aleksandra Nenadic
* 'rails3' of github.com:myGrid/biocatalogue:
  Fix for generating stats to work when there are are no services. Added delayed_job confing file as we should be using script/delayed_job instead of script/worker.