v1.4.0

This is entirely an upstream dependency-shifting release. If you're just using "shims" % "1.3.0" or "shims" % "1.3.1", there are no visible changes whatsoever. The primary change here is in shims-effect, which was downgraded from cats-effect 1.0.0-RC2 to cats-effect 0.10.1. This was done because cats-effect 1.0.0-RC2 is still unstable and its associated ecosystem (including fs2) is the same, and so it seems a lot more useful to have the primary dependency be 0.10.1. The shims version bump to 1.4.0 reflects the technical incompatibility of this change, even though I doubt anyone is going to feel much pain from this.