Add support for different docker directory

Author: Leonidas Tsampros

docker/map.jinja

@@ -3,6 +3,7 @@
         'pkg': 'lxc-docker',
         'pkg_version': '1.6.2',
         'py_version': '1.2.2',
+        'datadir': '',
     },
     'default': 'Debian',
 }, merge=salt['pillar.get']('docker',{})) %}

docker/templates/docker/default

@@ -1,10 +1,14 @@
+{% from "docker/map.jinja" import docker with context %}
 # Docker Upstart and SysVinit configuration file
 
 # Customize location of Docker binary (especially for development testing).
 #DOCKER="/usr/local/bin/docker"
 
 # Use DOCKER_OPTS to modify the daemon startup options.
 #DOCKER_OPTS="--dns 8.8.8.8 --dns 8.8.4.4"
+{% if docker.datadir %}
+DOCKER_OPTS="${DOCKER_OPTS} -g {{ docker.datadir }}"
+{% endif %}
 
 # If you need Docker to use an HTTP proxy, it can also be specified here.
 #export http_proxy="http://127.0.0.1:3128/"