Merge pull request #146 from sethryder/master

add IUS

README.md

@@ -662,6 +662,7 @@ Various resources, such as books, websites and articles, for improving your skil
 ### RPM-based distributions
   * [ElRepo](http://elrepo.org/tiki/tiki-index.php) - Community Repo for Enterprise Linux (RHEL, CentOS, etc).
   * [EPEL](https://fedoraproject.org/wiki/EPEL) - Repository for RHEL and compatibles (CentOS, Scientific Linux).
+  * [IUS](https://ius.io/) - Community project that provides RPM packages for newer versions of select software for Enterprise Linux distributions.
   * [Remi](http://rpms.famillecollet.com/) - Repository with LAMP updated packages for RHEL/Centos/Fedora.
   * [Software Collections](https://www.softwarecollections.org) - Community Release of [Red Hat Software Collections](https://access.redhat.com/documentation/en/red-hat-software-collections/). Provides updated packages of Ruby, Python, etc. for CentOS/Scientific Linux 6.x.