fixes launching with sim-launcher

The problem was with a call to a recently deprecated run-loop API
removed another call to run-loop deprecated API
Merge pull request #475 from calabash/feature/fix-launching-with-sim-launcher

fix launching with sim launcher
when testing, download dylib until server has build targets [skip ci]

The dylib tests are not run in CI yet; they are too unstable for
Travis CI.  This change helps local testing by ensuring the dylib is
not a 'fake' dylib generated by a previous step.
accessibility tests are in run-loop now
accessibility tests are in run-loop now
deprecate enable_accessibility_on_simulators
deprecated the enable access. SimulatorAccessibility API