These tests run each time Travis builds, causing additional noise and a
(negligible) speed decrease. However, since the advent of internal
plugins, these tests are unnecessary, and each file only carries a
package declaration anyway - so there are no tests actually executed!
Only the azure_instance is fully working (for both Linux and Windows
instances) now, but needs some tests. network and disk and pretty much
empty, but the idea is clear so will not take too much time…
James Nugent