Fixed issue with uncommon random failures cloning from The Workshop.
Some users reported encountering random failures in the cloning
operation from The Workshop.
The most common install method in practice is to pull the latest
SDP release from the mainline. This does not require cloning, so
changing the default install method to tarball (see job HI-19) for
the most common scenario eliminates the random cloning issue
(believed to be some kind of random Workshop network issue). This
eliminates that issue and is also faster.
When pulling from the dev branch, cloning is required, to enable
getting the the very latest submitted code and even shelved files.