RELENG-228: a git-managed version of the build step for <https://jenkins.joyent.us/job/mg/configure>
RELENG-228: a git-managed version of the build step for <https://jenkins.joyent.us/job/mg/configure>

The previous version was using ">>" instead of "tee -a". Trying tee
for a cleaner jenkins log.

joyent/mountain-gorilla,joyent/mountain-gorilla,joyent/mountain-gorilla