Bind console methods to original instance to retain source line information

[lachieh]

I noticed that the console methods all print the source as __x00__virtual:console-forward:115 in the browser console. By binding the method to console object as the this context, the correct source information is preserved.

Nevermind, it's still not behaving the way it should. Reverting to draft for now...

Also added a sneaky update to the README.md that fixes #2.

[lachieh]

Turns out the only way to prevent this is to either add a sourcemap and ignore it using the x_google_ignoreList property, or to manually ignore this script using the browser.

I'm going to close this for now, but I do have a solution that generates the correct sourcemap and ignores it from the browser debugger.

Hat tip to this blogpost: https://anthonykuske.com/how-to-extend-console-log-and-keep-the-correct-filename-and-line-numbers-shown-in-the-console/