Add a .dockerignore to make image builds faster.
Add a .dockerignore to make image builds faster.

dlorenc/minikube,r2d4/minikube,warmchang/minikube,dims/minikube,kubernetes/minikube,dlorenc/minikube,dlorenc/minikube,dlorenc/minikube,dims/minikube,r2d4/minikube,warmchang/minikube,warmchang/minikube,aaron-prindle/minikube,kubernetes/minikube,dalehamel/minikube,dalehamel/minikube,kubernetes/minikube,kubernetes/minikube,dlorenc/minikube,dlorenc/minikube,aaron-prindle/minikube,aaron-prindle/minikube,dalehamel/minikube,dlorenc/minikube,r2d4/minikube,warmchang/minikube,kubernetes/minikube,kubernetes/minikube,kubernetes/minikube,warmchang/minikube,dlorenc/minikube,dims/minikube,warmchang/minikube,warmchang/minikube