Changes the file-based protocol for controlling when stepdowns are
permitted to be a one-shot mechanism usable only once during a test.
That is to say, the indication for whether the stepdown thread isn't
currently and will no longer continue to run stepdowns during the test
persists until after the test finishes.
Change resmoke.py to wait up to 5 minutes for a mongod/mongos process
to start accepting connections. Waiting only 30 seconds for a
connection to be established is insufficient on some build variants in
Evergreen. This is likely due to file preallocation, disk speed, and
other resource factors.
Split out the passthrough tests into separate suites. The MongoDB
deployment is started up by resmoke.py so that we can record the
success/failure of each individual test in MCI.
Added support for parallel execution of tests by dispatching to
multiple MongoDB deployments.
Added support for grouping different kinds of tests (e.g. C++ unit
tests, dbtests, and jstests) so that they can be run together. This
allows for customizability in specifying what tests to execute when
changes are made to a particular part of the code.
