If you already have a working PostgreSQL 9.5 install, and just want to skip to relevant sections, follow this list:
As a general note, these instructions are what I did for CentOS 7. For lower versions ther are some differences in packages you'll get.
For example currently if you are installing on CentOS 6 (and I presume by extension other 6 family), you won't get SFCGAL and might have pgRouting 2.0 (instead of 2.1)
