Amalgamate v0.1.0

• Tidy package.json. See #65.
• Test adding many items. See #62.
• Test merge and iterate over items. See #62.
• Upgrade dilute to 2.0.0-alpha.3. Closes #67.
• Add chicklets to README.md. Closes #65.
• Add .npmignore. See #66.
• Convert README.md to Markdown. See #65.
• Update LICENSE for 2020. Closes #66.
• Build with Actions, ship coverage to Codecov. Closes #63. Closes #64.
• Update .gitignore. See #65.
• Build only with Node.js 12 on Travis CI. See #65.
• Remove checked in temp files. See #65.
• Convert open and close. See #62.
• Update rimraf to 2.4.3.
• Upgrade Proof to 0.0.56.
• Fix license field in package.json.

Closes #68.