fix: [docker-host] soften constraint on ``docker-compose`` exact version string

We had the build number changing from ``a133471`` to ``unknown``.

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

@@ -176,16 +176,17 @@ sysctl -w net.ipv4.ip_forward=1
 
 if type -p docker-compose >/dev/null; then
     #echo "Found docker-compose..." >&2
-    if ! docker-compose --version >/dev/null 2>&1; then
+    if ! CURRENT_VERSION_TEXT="$(docker-compose --version 2>/dev/null)"; then
         echo "'docker-compose' failed ! Please check your docker-compose binary."
         echo "Failed install."
         docker-compose --version
         exit 1
     fi
-    VALID_VERSION_TEXT="docker-compose version 1.21.2, build a133471"
-    if [ "$(docker-compose --version)" != "$VALID_VERSION_TEXT" ]; then
+    VALID_VERSION_TEXT="docker-compose version 1.21.2, build "
+    if ! [[ "$CURRENT_VERSION_TEXT" == "$VALID_VERSION_TEXT"* ]]; then
         echo "Invalid version of docker-compose: we need exactly:"
-        echo "version text: $VALID_VERSION_TEXT"
+        echo "version text:    $VALID_VERSION_TEXT"
+        echo "current version: $CURRENT_VERSION_TEXT"
         echo "Failed install."
         exit 1
     fi