feature(helpers): allow specifying tag

helpers/ab-nginx.params.template

@@ -6,6 +6,22 @@
 ###
 
 
+#
+# Container options
+#
+
+# Specify a particular tag to 'version pin' the ab-nginx container.
+#TAG=latest
+
+# Specify a runtime UID and GID for the container user. This is useful to
+# ensure the container can read and/or write to locations on the host or
+# has access to files shared between members of a container stack.
+# REQUIRED: NO
+# DEFAULT: UID=8080, GID=8080
+# VALID OPTIONS: any permissible and available UID/GID value
+#UID=8080
+#GID=8080
+
 #
 # Network options
 #