"yarn install" installs tape with breaking changes

[PaulTomchik]

The project README's Development Install instructions specify using yarn.
However, the project includes a package-lock.json and no yarn.lock.
Additionally, the project's package.json uses the wildcard for the tape version.

As a result, yarn install installs version 5.0.1 of tape, while npm install installs version 4.10.1.

Tape v5.0.0 included a breaking change for the deepEqual function (tape-testing/tape#508).

This breaking change causes the "tiles -- build tile paths " tests to fail in test_code.ts.

yarn import generates the yarn.lock file that fixes the problem.