Made epicsThreadOnceTest more deterministic, replacing an
epicsThreadSleep() with epicsEventMustWait(), and added a diagnostic
message before running the thread recurse test.
Eric added a series of checks to epicsEventTest.cpp which ensure that
epicsEventSignal() only wakes one waiting thread.
Removed all Main.cpp files, use the macro in testMain.h instead and
defaulted all argc/argv parameters.
Converted all real test programs to use epicsUnitTest.h.
Moved performance measurements from epicsThreadTest to epicsThreadPerform.
Moved epicsOkToBlockTest tests into epicsThreadTest.
On a host arch, make test inside the O.arch directory runs all tests.
