fix: [docker-host] default project name wouldn't have dynamic resolution and would not be lowercase

``docker-compose`` doesn't like lowercase for project name.

precise/host/hooks/install.d/70-0k.sh

@@ -197,7 +197,8 @@ cat <<EOF > /etc/default/compose
 ## if not provided, this will be the default service launched.
 export DEFAULT_SERVICES=""
 
-export DEFAULT_PROJECT_NAME=$(hostname | cut -f 2 -d . )
+export DEFAULT_PROJECT_NAME=\$(hostname | cut -f 2 -d . )
+DEFAULT_PROJECT_NAME=\${DEFAULT_PROJECT_NAME,,}  ## to lowercase
 
 export DOCKER_DATASTORE=\$([ -e /etc/default/datastore ] && . /etc/default/datastore && echo \$DATASTORE)
 export DATASTORE=\$DOCKER_DATASTORE/data