Make race detection configurable

Make race detection configurable to facilitate faster local test
iteration using the standard test script. By default, race detection
is enabled.
Merge pull request #155 from ironcladlou/race-detection-flag

Merged by openshift-bot
Make race flag override match upstream

Use the upstream convention for overriding the -race flag.
Merge pull request #156 from ironcladlou/race-detection-flag

Merged by openshift-bot