Add -r/--release to kali template

Signed-off-by: Sébastien Delafond <sdelafond@gmail.com>

templates/lxc-kali.in

@@ -608,7 +608,7 @@ EOF
     return 0
 }
 
-options=$(getopt -o hp:n:a:cI:FS: -l arch:,auth-key:,clean,help,enable-non-free,mirror:,name:,packages:,path:,rootfs:,interpreter-path:,flush-cache -- "$@")
+options=$(getopt -o hp:n:a:r:cI:FS: -l arch:,auth-key:,clean,help,enable-non-free,mirror:,name:,packages:,path:,release:,rootfs:,interpreter-path:,flush-cache -- "$@")
 if [ $? -ne 0 ]; then
         usage "$(basename "$0")"
         exit 1
@@ -647,6 +647,7 @@ do
         -n|--name)            name=$2; shift 2;;
            --packages)        packages=$2; shift 2;;
         -p|--path)            path=$2; shift 2;;
+        -r|--release)         release=$2; shift 2;;
            --rootfs)          rootfs=$2; shift 2;;
         -F|--flush-cache)     flushcache=1; shift 1;;
         *)                    break ;;
@@ -718,7 +719,7 @@ if [ -n "$authkey" ]; then
     fi
 fi
 
-release=kali-rolling
+release=${release:-kali-rolling}
 
 # detect rootfs
 config="$path/config"