Add ExternalRunnerTest; attempt to handle Run problems

Apparently vim integration *doesn't* work consistently. Added the
ExternalRunnerTest to try to have a tighter testing environment,
but it seems to work just fine there. Not sure why threads seem
to finish early in the production environment....
Fix timeout issue... with longer timeout; fix quotes in output

Not sure why but 1.5s seems to be the magic number. Weirdly,
other calls take significantly less time....