Use chokidar@3, 0.9.7

Fix typo in usage output, 0.9.6

@atom/watcher back to v1, 0.9.5

Update for Node@10 until watcher release is cut, 0.9.4

Revert "Add debounce option to node api, 0.9.2", 0.9.3

This reverts commit 8c150de.