Fixed flaky FaultToleranceTest.SchedulerFailoverStatusUpdate.

From: Jiang Yan Xu <yan@jxu.me>
Review: https://reviews.apache.org/r/15946
Fixed ./bootstrap to handle AUTOMAKE and ACLOCAL environment
variables.

See: MESOS-849

From: Bernardo Gomez Palacio <bernardo.gomezpalacio@gmail.com>
Review: https://reviews.apache.org/r/15862