Updates for python36 and scl

source/_docs/installation/centos.markdown

@@ -11,37 +11,48 @@ footer: true
 
 To run Python 3.x on [CentOS](https://www.centos.org/) or RHEL (Red Hat Enterprise Linux), [Software Collections](https://www.softwarecollections.org/en/scls/rhscl/rh-python36/) needs to be activated first.
 
-You must install Python 3.5.3 or later. Software Collections version of Python 3.5 is 3.5.1 so this guide uses Python 3.6.
-
 ### {% linkable_title Using Software Collections %}
 
-First of all install the software collection repository as root. For example, on CentOS:
+First of all install the software collection repository as root and [scl utils](https://access.redhat.com/documentation/en-US/Red_Hat_Developer_Toolset/1/html-single/Software_Collections_Guide/). For example, on CentOS:
 
 ```bash
-$ yum install centos-release-scl
+$ sudo yum install centos-release-scl
+$ sudo yum-config-manager --enable centos-sclo-rh-testing
+$ sudo yum install -y scl-utils
 ```
 
 Install some dependencies you'll need later.
 
 ```bash
-$ yum install gcc gcc-c++ systemd-devel
+$ sudo yum install gcc gcc-c++ systemd-devel
+```
+
+Then install the Python 3.6 package. If you are using CentOS 7 then you may have to install the packages for Python 3.6 using RHEL Methods listed here: https://www.softwarecollections.org/en/scls/rhscl/rh-python36/) for this to work as mentioned above.
+
+```bash
+$ sudo yum install rh-python36
 ```
 
-Then install the Python 3.6 package:
+This is part of the slight change when trying to install Python 3.6 and running the command `python36 --version` which will after install give you the correct version, but won't allow you to set the software collection using the `scl` command. This command downloads the RH collection of Python to allow you to run `scl` command to enable the environment in `bash` and then run the automate command using the template.
 
 ```bash
 $ yum install rh-python36
 ```
 
-Once installed, switch to your `homeassistant` user (if you've set one up), enable the software collection and check that it has set up the new version of Python:
+### {% linkable_title Start using software collections %}
 
 ```bash
 $ scl enable rh-python36 bash
+```
+
+Once installed, switch to your `homeassistant` user (if you've set one up), enable the software collection and check that it has set up the new version of Python:
+
+```bash
 $ python --version
 Python 3.6.3
 ```
 
-You will be in a command shell set up with Python 3.6 as your default version. The virtualenv and pip commands will be correct for this version, so you can now create a virtual environment and install Home Assistant following the main [instructions](/docs/installation/virtualenv/#step-4-set-up-the-virtualenv).
+You will be in a command shell set up with Python 3.6 as your default version. The `virtualenv` and `pip` commands will be correct for this version, so you can now create a virtual environment and install Home Assistant following the main [instructions](/docs/installation/virtualenv/#step-4-set-up-the-virtualenv).
 
 You will need to enable the software collection each time you log on before you activate your virtual environment.