Allow empty vars in safe mode

[mkrause]

In #14, empty variables were allowed, but only in non-safe mode. But even in safe mode we'd often like to use an empty string as a possible value. Can we make a distinction between .env variables that are not specified as opposed to variables that are just empty?

# .env.example
FOO=default
BAR=default

# .env
FOO=

The lack of BAR should result in an error, FOO should not.

Also worth noting that dotenv-safe allows empty values, configurable through an "allowEmptyValues" option.

[mrsteele]

Hmmmm, Yeah if dotenv-safe supports that we should probably too, but I think it should be configurable just like dotenv. Any chance you wanna make a go at it?

[mkrause]

Sure! I just submitted PR #134. I've added an option allowEmptyValues (default false), similar to dotenv-safe.

[mkrause]

@mrsteele Do you think you'll have time to review?

[nusson]

Any update on this ?

[marcofugaro]

Is this repo dead? This feature is actually useful

[mrsteele]

Anyone willing to resolve the conflicts?

[marcofugaro]

If @mkrause is not available, I am willing to make a new PR with the old one's content.

[mkrause]

I can fix the conflicts. Over the weekend maybe.

[mkrause]

Updated the PR