Auto merge of #471 - aneeshusa:add-vagrant-version-upper-bound, r=metajack
Auto merge of #471 - aneeshusa:add-vagrant-version-upper-bound, r=metajack

Add Vagrant version upper bound of "< 1.8.3"

A recent PR to Vagrant, which is in released 1.8.3+, breaks our usage of
`minion_id` to pass additional args to Salt.
See https://github.com/mitchellh/vagrant/pull/7207 for the PR.

Also add comments in the Vagrantfile about the version requirements.

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