Merge pull request #1458 from janestreet/master

fix the remove field of typerep.109.55.00
Release mirage-block-unix.1.2.0 and fat-filesystem.0.10.0

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #1459 from djs55/mirage-block-unix.1.2.0

Release mirage-block-unix.1.2.0 and fat-filesystem.0.10.0
jenga 109.55.03