add support for Microsoft Edge

[yudukikun5120]

Motivation

Microsoft Edge is a new browser from Microsoft. It is based on Chromium and is available on Windows 10 and macOS. It occupies a certain market share (about 4%^1) and is used mainly by Windows users. It would be nice to support it.

Proposed solution

• [x] ~~Port a Chrome extension to Microsoft Edge~~ This looks already done as I tried it and succeeded. Also, see this article.
• [ ] #8
• [ ] Submit the extension to Microsoft Edge Add-ons Store according to this guide

The developer name of the submitter would be better if it is the same as the one of the Chrome Web Store, so I'd like to request @mkobayashime to do it. Any supports are welcome.