.ruby-version not working for 2.1.10

[HoneyryderChuck]

I have multiple 2.1.x versions installed, including 2.1.8 and 2.1.10 .

If my .ruby-version contains 2.1, it automatically switches to 2.1.8, although I'd be expecting 2.1.10

[deivid-rodriguez]

I'd say this is a dup of #363