Updated readme with link to postgres installation tutorial

[monfresh]

Hi,
This is Moncef (2013 CfA Fellow). I wrote a tutorial for installing Postgres on a Mac with Homebrew and linked to it in the Readme.

I also added "gem update bundler" to the instructions because I got errors when running "bundle install". Updating bundler solved the problem.

[sferik]

Hi Moncef,

It makes me very happy to see a new class of Code for America Fellows taking an interest in this project.

That being said, I haven’t merged this pull request. Let me try to explain why…

Adding gem update bundler to the README would have solved your particular problem. But imagine if you also had an outdated version of rubygems. Why not also add the command gem update --system? Now, imagine if you were using an outdated version of Ruby. Why not also link to the full instructions on how to install the latest version of Ruby?

This reminds me of one of my favorite quotes:

If you want to make an apple pie from scratch, you must first create the universe.
–Carl Sagan

To write a useful recipe, I need to assume certain things about the reader. In this case, I’m assuming readers will be running a modern version of bundler, on a modern version of Ruby, on a modern operating system, on a modern computer, that’s connected to the Internet, on the planet Earth, etc., etc., etc. Otherwise, the README might begin:

Fly your spaceship to Earth, the third planet from Sol, between Alpha Centauri and Proxima Centauri. Land your ship on or around flat, solid ground. Be particularly wary of landing in the Pacific Ocean. Earth Lesson 1: names can be misleading. Welcome to Earth! Now, find a human and exchange approximately 0.15 moles of the chemical element with the atomic number 79 for a Turing machine…

Maybe I’m assuming too much, but I don’t think it’s the responsibility of this project to ensure that users are running the latest version of bundler, just as this project doesn’t explain how to get to Earth or buy a computer or write a computer program.

If the bundle install command fails, I’d expect most users to think: “Maybe I’m not using the right version of bundler. Let me check what version I’m using. Maybe I’ll upgrade and try again.”

As it turned out, this was roughly the process you went through. Perhaps you tried a few other things first and it would have saved you some time to have that particular instruction in the README, but it would be a waste of time for everyone using a recent version of bundler, so that’s the tradeoff.

[monfresh]

Thanks for your entertaining comment :) I completely agree. I understand now that there are certain environment assumptions that are different from app-specific requirements such as having Postgres installed.

Speaking of Postgres, you didn't address that part of my pull request. Would you accept having a link to my Postgres installation tutorial in the README?