Moved the integration test of HelloREEF into reef-tests

Closes #961

Also, this moves some common code of all tests into TestEnvironment
Added the HelloREEF test to the TestSuite
Merge pull request #968 from Microsoft-CISL/weimer_961

Moved the integration test of HelloREEF into reef-tests
add driver restart completed event
typo fixes
Merge branch 'yingdac-restart-complete-handler' into reef-bridge
add driver restart handler
add restart completed handler to driver configuration
Merge branch 'yingdac-restart-complete-handler' into reef-bridge