Fix bugs for installing docker, bug #1237581.

-The change in install_docker.sh corrects a typo ('=' should be '-').
   This typo resutls in 'unable to locate the packet' error when executing apt-get.

  -The second change is in hypervisor-docker fix the error for reporting
   docker is not installed when docker is actually set up. The original line
   missed the version part of the package name.

Change-Id: Ic48f45158cf84f89080f095d53c355e9f6969bfd

lib/nova_plugins/hypervisor-docker

@@ -72,7 +72,7 @@ function install_nova_hypervisor() {
     fi
 
     # Make sure Docker is installed
-    if ! is_package_installed lxc-docker; then
+    if ! is_package_installed lxc-docker-${DOCKER_PACKAGE_VERSION}; then
         die $LINENO "Docker is not installed.  Please run tools/docker/install_docker.sh"
     fi
 

tools/docker/install_docker.sh

@@ -38,7 +38,7 @@ curl https://get.docker.io/gpg | sudo apt-key add -
 install_package python-software-properties && \
     sudo sh -c "echo deb $DOCKER_APT_REPO docker main > /etc/apt/sources.list.d/docker.list"
 apt_get update
-install_package --force-yes lxc-docker=${DOCKER_PACKAGE_VERSION} socat
+install_package --force-yes lxc-docker-${DOCKER_PACKAGE_VERSION} socat
 
 # Start the daemon - restart just in case the package ever auto-starts...
 restart_service docker