Update to Deno v0.21.0

Use TLA in README

Update to Deno 0.19

Update CI to Deno 0.17

Update to Deno v0.16

Update to Deno 0.15

Update to Deno 0.12

Update to Deno 0.9.0, including std.

Update README and examples.

Bump CI to 0.2.11