Document what is meant by `'./path-to-your/.env'`

(ie path begins with `./` or `../` and is relative to the package.json or run directory)

It is non-intuitive within a complex file structure whether env vars are failing to load due to the wrong path being included or due to:
```
�[1m�[43m�[30m WARNING: �[22m�[42m�[30m env2 was required to load an .env file: �[46m�[30m ./.env �[1m�[43m�[30m INVALID JSON! �[22m�[42m�[30m Please see: http://git.io/vG3UZ�[49m�[39m�[22m
```
Documenting the above would help.