Please create a tag for the work currently in master

[jmadson]

Thank you for this awesome validation library! Could somebody please create a tag for the work currently sitting in master?

Looking at the git commit history, it looks like there were type validators which were added at the end of 2017, but the most recent tag, 0.12.0, does not have that work and there have not been any commits in the 5 months since.