Update readme with information on env vars

[arruda]

The example.env allows the easy and ready to use single machine localhost deployment. But when deploying in a way that allows for access from more than just the host machine (localhost), then the sys admin deploying the services should know which env vars they need to replace.

I believe that right now these should be all the env vars that have 'localhost' in them, which should be changed to whichever is the external IP or DNS that will be used to access the host machine running all the docker containers.

Other more complex deployment environment goes outside of the scope of this, ie: if someone wants to deploy in machine A only the FC, and have it connected to the rest of the open agri ecosystem that is deployed in machine B.

[fedjo]

Can you elaborate on this @arruda ? Do we still need it?

[arruda]

I think we still need to improve the docs, at least to mention that by default the bootstrap repo example.env is set for a ready-to-use localhost setup.