Allow scheme config from env vars

[arielectron]

Hi Erik.

I hope you are doing well.

I suggest this changes for allow to Docker users to configure the schema of the connection.

Thanks.
Ariel.

[arielectron]

Two ways for config the scheme:

URL mode:
REDIS_1_HOST=tls://host:port

whithout config REDIS_1_PORT nor REDIS_1_SCHEME

Host mode:
REDIS_1_HOST=host
REDIS_1_PORT=port
REDIS_1_SCHEME=tls

[erikdubbelboer]

Thanks!