feat: Use environment variables or config file for app configuration

[dmvict]

Proposition

Add support of configuration variables or configuration file to configure the application behavior.

Problem

I tried to use updated application and got non intuitive error:

Error: could not find key ring at /home/work/.ultradao/keyring-file

The reason of the error is that I added keyring using option

--keyring-backend test 

And the other commands required the option but I used no option.

The problem is solved by @joneskm.

By the way, it should be useful to have some configurations in app configuration file or environment variables. For example, it can be .env (app.json, app.toml, etc.) file or variables prefixed by GEARS_ (GEARS_KEYRING_BACKEND).