Responsive continuous builds on macOS and Windows on Java 9+

[pioterj]

Use the file system watching infrastructure to make the continuous build feature more robust.

One of the practical outcomes of doing this is that continuous builds on macOS and Windows on Java 9 and later will react to file changes almost instantly, as opposed to the current delay that can be as long as 10 seconds between file change and new build being triggered.

Related issues:

• Continuous build responsiveness is too slow on mac gradle#3427
• Use same infrastructure for VFS retention and continuous build gradle#11834