Fixes harmless error message in yum repo

If yum repo is missing a name, then anytime you try and install a program with yum, you will get the error " Repository 'logstash' is missing name in configuration, using id "

Counter intuitively, you must use 'descr' instead of 'name' 
https://groups.google.com/forum/#!topic/puppet-users/QEM0XquEyLY