Native doesn't build with base v0.14.0

[fabrizzioalco]

Trying to tun the project show me this error:

So to run the project you should downgrade the base to v0.13.2 with this
opam pin add base v0.13.2

This would downgrade the base and being able to run it

[Dean Merchant]

Thanks @fabrizzioalco.

[Paul Biggar]

Fixed in #220