Wget recursive option not working correctly with scheme relative URLs

[Jan Bidler]

Hello,
I have part of a website (`example.com/index.html`) I want to mirror which 
contains scheme relative URLs (`//otherexample.com/image.png`). Trying to 
download these with the -r flag, results in wget converting them to a wrong URL 
(`example.com//otherexample.com`).

So using
`wget -r example.com/index.html`
Will cause links with 
`https://example.com/index.html\/\/otherexample.com\/image.png` in the output
Using the debug flag reveals this:
`merge(»example.com/index.html «, » //otherexample.com/image.png«) -> 
https://example.com/index.html\/\/otherexample.com\/image.png 
[`](https://example.com/index.html//otherexample.com/image.png`)