[INSTALL] Adding script to install docker (Debian).

install/docker.install

+#!/bin/bash
+
+sudo apt-get update
+sudo apt-get install \
+     apt-transport-https \
+     ca-certificates \
+     curl \
+     gnupg2 \
+     software-properties-common
+
+curl -fsSL https://download.docker.com/linux/debian/gpg | sudo apt-key add -
+sudo apt-key fingerprint 0EBFCD88
+echo "Should be: Key fingerprint = 9DC8 5822 9FC7 DD38 854A  E2D8 8D81 803C 0EBF CD88"
+
+sudo add-apt-repository \
+   "deb [arch=amd64] https://download.docker.com/linux/debian \
+   $(lsb_release -cs) \
+   stable"
+
+sudo apt-get install docker-ce
+sudo docker run hello-world