Suricata

We currently have advanced installation guidance (from Git) on redmine: https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Ubuntu_Installation_from_GIT

As we're trying to move the documentation redmine from to read the docs, it would be good to have this in our devguide, too.

When we do that, also see if any steps should be updated.
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Report from someone from our community, that should be covered by this ticket:
"Following [this post](https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Ubuntu_Installation_from_GIT) to build suricata, I noticed that there was a suricata-update directory in the parent suricata directory already, and following the commands detailed [here](https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Ubuntu_Installation_from_GIT#:~:text=To%20install%20suricata-update) prompted a git error fatal: destination path 'suricata-update' already exists and .... I think there should be changes to the documentation since suricata-update has been added to the newer version of suricata, right? (or atleast indicate that newer version have suricata-update by default, and detail how to set it up)"