Docker tag 6 to be used by default in installer and in dockerhub

Change-Id: I637a32d63f171773ad947d4dd2373b1a04f1b28c
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>

docker/mk/Makefile.include

@@ -4,7 +4,7 @@ MKBUILD=$(TOPDIR)/docker/build
 
 all: build
 
-TAG ?= 5
+TAG ?= 6
 
 REPOSITORY_BASE ?= http://osm-download.etsi.org/repository/osm/debian
 RELEASE         ?= ReleaseFOUR-daily

installers/install_osm.sh

 #!/bin/bash
 REPOSITORY_BASE=https://osm-download.etsi.org/repository/osm/debian
-RELEASE=ReleaseFIVE
+RELEASE=ReleaseSIX
 REPOSITORY=stable
+DOCKER_TAG=6
 
 add_repo() {
   REPO_CHECK="^$1"
@@ -31,4 +32,4 @@ add_repo() {
 add_repo "deb [arch=amd64] $REPOSITORY_BASE/$RELEASE $REPOSITORY devops"
 sudo DEBIAN_FRONTEND=noninteractive apt-get -q update
 sudo DEBIAN_FRONTEND=noninteractive apt-get install osm-devops
-/usr/share/osm-devops/installers/full_install_osm.sh -R $RELEASE -r $REPOSITORY -u $REPOSITORY_BASE -D /usr/share/osm-devops -t latest "$@"
+/usr/share/osm-devops/installers/full_install_osm.sh -R $RELEASE -r $REPOSITORY -u $REPOSITORY_BASE -D /usr/share/osm-devops -t $DOCKER_TAG "$@"