Add instructions for using PostgreSQL 9.5 installed via Homebrew

[charles-cowart]

To support a commonly used method to install PostgreSQL on MacOSX.

[antgonza]

@charles-cowart, just to confirm, this issue is to add this line somewhere in the documentation, right?

[charles-cowart]

I would work more from https://medium.com/@Umesh_Kafle/postgresql-and-postgis-installation-in-mac-os-87fa98a6814d as an example, just because (if you haven't done it before), starting up with pg_ctrl, initializing a database with initdb, and set the service to start on boot w/launchd (brew services start postgresql) are also important.

[charles-cowart]

Happy to do this, if you need.

[antgonza]

Got it, the current instructions suggest using Postgres.app, which does all that for you for free! Anyway, what about just linking that document?

[charles-cowart]

The blog post? That doesn't sound like a good idea. I can add a few lines, it's no trouble.

[antgonza]

Yup, the blog post. Anyway, assigning to you and if you use those instructions are a reference, please don't forget to cite ...

[antgonza]

We currently have detailed instructions for the Postgres.app, which works just fine. If a dev wants to install using any other methods: installing from source, homebrew, apt-get, etc, it's because that's what they normally use so the need for detailed instructions on those other methods is not required; and perhaps impossible to cover them all. However, we welcome any improvements to the documentation so if you want to add it, please do so! Thank you @charles-cowart.