v0.8.0

More modern Node requirement, file upload support.

• BREAKING CHANGE: m3api now requires at least Node.js version 18.2.0, up from Node 12.22.0 or Node 14.17.0 previously. The internal breaking changes below are also related to this.
• Internal Breaking Change: The file add-performance-global.js has been removed, as it is no longer needed.
• Internal Breaking Change: The file axios.js has been removed, as axios is no longer used. Its role has been taken over by fetch-node.js.
• Internal Breaking Change: The file fetch.js is no longer suitable for use in Chrome-like browsers. The functionality of renaming the user-agent request header to api-user-agent has been moved to fetch-browser.js.
• m3api now uses fetch() on all supported platforms. The public interface, browser.js and node.js, can be used as before. The internal interface has been rearranged, with fetch.js now used for both backends, augmented by fetch-browser.js and fetch-node.js.
• m3api now supports Blob and File parameters in POST requests. This can be used to upload files.
• Improved README.md formatting for npmjs.com.
• Updated dependencies.