Be able to switch-off ASAN builds of our binaries.

Inroduce a way to not take a 2x performance hit when testing. It
is of importance if we run with hundreds of BTSes and 10k+ subscribers.
In the absence of using getops or shflags use an environment for it.

Change-Id: I540ba1c35e8fb72abcee0d86e0bdc1136b47345c
12 files changed