* Fix Berkeley mentions
* Add new collectors to list
* Tweak Prometheus/OpenMetrics phrasing
* Fix heading depth in performance guide
* Clarify that exporting starts with Agent start
* Clarify usage of edit-config with new files
* Update images
* service -> systemctl
* Reverse systemctl order
* Finish new common config doc, delete old one
* Small tweak to blockquote
* Add new files
* Fix broken links
* Fix one more broken link
* Copyedits and improvements
* Fix broken link
* Re-add common config doc
* service -> systemctl
* Reverse systemctl order
* Add mention of .conf files in health.d
* Add mention of minimum global update every
* Init guide
* Working on guide
* Finish first draft of performance guide
* Retitle and fix links in other docs
* Acutally add guide
* Copyedit pass
* Fixes for Amy
