Not clear in README what is postgresql is for

[rjlanari]

I found that in the README it is not clear what is postgresql used for. Should it be added to the README ?

[t-j-q]

I found that in the README it is not clear what is postgresql used for. Should it be added to the README ?

@rjlanari Yes, if you'd be so kind :)

[t-j-q]

@rjlanari Have you added this to the readme yet?