Simplify VM scripts for release

4.4 and 5.0 release jobs have been using
https://gist.github.com/joshmoore/6902157
for some time. Primarily, this patch uses
an existing server zip rather than attempting
to download from a job.
Merge pull request #1968 from joshmoore/rebased/dev_5_0/vm-patch-4.4

Simplify VM scripts for release (rebased onto dev_5_0)