Add support for loading username and password from environment

[acez]

Hello,

thanks for your great tool. I want to use it in a docker based environment and need to supply username and password via the environment.
This allows to load username and password from environment variables specified in the config. It is implemented in the same non-breaking way as bcrypt support. I added an example in the readme.

Best,
Christian

[hacdias]

Thanks and sorry for taking so long merging this :(

[kuro7766]

I'm new to this repo and I think it's a bad design. I have met the same problem like #83 because of this merge.
Here is what I have done:

• Copy yml file in README.md to ./
• run binary file with no params

but throws an error

the environment variable is empty

And this solves my problem. Just remove those {env} statements.

Add trouble for beginners to understand and config. Or this should not be the default behaviour.

[acez]

@kuro7766 This was just an example to show what is possible and how the feature is working.
Removing {env} from the string just disables the feature to get the data from the environment - but also enables login with username "ENV_USERNAME" and password "ENV_PASSWORD".
You can just remove both lines and you'll be fine.