[PR Feedback] Update IMAGE_TAG documentation to account for "dev"
# IMAGE_TAG is the "master variable"; if it is set to something other
# than "latest", we will build images suitable for production
-# usage. If it is unset, or "latest", we'll be creating images for
+# usage. If it is unset, "dev", or "latest", we'll be creating images for
# local usage only.
#
# In general, you'll only set this (via an environment variable when
