Prolific Shuttle v27.0.0

• Upgrade prolific.evaluator to ^4.0.0. Closes #1318.
• Upgrade prolific.watcher to ^0.2.0. Closes #1317.
• Upgrade prolific.collector to ^12.0.0. Closes #1316.
• Upgrade prolific.queue to ^20.0.0. Closes #1315.
• Upgrade destructible to ^6.0.0. Closes #1314.
• Upgrade prospective to ^0.2.0. Closes #1313.
• Upgrade duplicitous to ^0.2.0. Closes #1312.
• Upgrade rimraf to 3.0.2. Closes #1311.
• Upgrade proof to ^9.0.1. Closes #1310.
• Update LICENSE for 2020.

Closes #1319.