Support OSX Edge

[krotscheck]

Edge is now available on OSX: https://www.microsoftedgeinsider.com/en-us/download

It'd be nice if we could run tests against it :)

[SteffenAnders]

bump

[shirshak55]

If possible please support it :)

[jameswomack]

@chiragrupani/karma-chromium-edge-launcher supports Edge macOS in my testing