Docker install script complains about unset locale

[sp4ghet]

scripts/install_docker.sh fails when the locale is unset in the raspi. We should figure out a way to set a default locale if the locale is unset in the raspberry pi in the install_docker.sh script.

[ghost]

I'm pretty sure there's an issue where gordon and I were discussing how to invoke raspi-config in non-interactive mode. I'll try to find a link to that stuff.

[ghost]

Found it. This was talking about enabling i2c, but I think the syntax could probably be adapted for raspi-config's locale screen.

https://github.com/OpenAgInitiative/openag_brain/pull/159#issuecomment-290231712

[sp4ghet]

I'll give it a try