mozilla/dxr — pull request #272 by uberj (2014-03-31 21:23:41+00:00)
Title: Only !merge local vagrant params when present

If vagrantconfig_local.yaml is empty `YAML.load()` will eval to false and upon
running `vagrant up` you will get the error: "ERROR loader: Vagrantfile load
error: no implicit conversion of false into Hash." This patch checks to make
sure some YAML was parsed before merging it.