Sensu yum repositories updated

This commit contains an update to the sensu Yum repositories. As
mentioned by @portertech in sensu/sensu##1062, sensu has moved their
repositories to new locations, although symlinking old paths in order to
preserve backward compatibility.

files/sensu-unstable.repo

@@ -1,5 +1,5 @@
 [sensu-unstable]
 name=sensu-unstable
-baseurl=http://repos.sensuapp.org/yum-unstable/el/$releasever/$basearch/
+baseurl=http://repositories.sensuapp.org/yum-unstable/$basearch/
 gpgcheck=0
 enabled=1

files/sensu.repo

@@ -1,5 +1,5 @@
 [sensu]
 name=sensu-main
-baseurl=http://repos.sensuapp.org/yum/el/$releasever/$basearch/
+baseurl=http://repositories.sensuapp.org/yum/$basearch/
 gpgcheck=0
 enabled=1