Add kubernetes support

[arshbot]

Currently the only way to use lnt is to connect it to a port that forwards or is listened to by the lnd daemon. Ideally there would also be kube support so you could specific the:

• context
• namespace
• pod
• container

you'd like to access and run commands against. Accessing down to the container would run lncli commands in the container and remove the need to host sensitive information ( such as macaroons ) locally