Auto merge of #240 - aneeshusa:ensure-minimum-vagrant-version, r=larsbergstrom
Auto merge of #240 - aneeshusa:ensure-minimum-vagrant-version, r=larsbergstrom

Ensure Vagrant version is at least 1.8.0

Use the Vagrant.require_version helper documented here:
https://www.vagrantup.com/docs/vagrantfile/vagrant_version.html

Eliminates issues like #238.

Heads up: I didn't test this with a Vagrant older than 1.8.0, so I have no idea if this actually works.
@larsbergstrom can you test this if possible since you ran into this?
I want to make sure this is actually a useful change.

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UK992/saltfs,UK992/saltfs,rwaweber/saltfs,setupminimal/saltfs,ALikhachev/saltfs,UK992/saltfs,setupminimal/saltfs,servo/saltfs,setupminimal/saltfs,rwaweber/saltfs,rwaweber/saltfs,ALikhachev/saltfs,ALikhachev/saltfs,servo/saltfs