Add a [bobbingwide] shortcode as shorthand alias for [github bobbingwide]

[bobbingwide]

Just a thought, having recently forgotten the shortcode name and gone straight into the parameters.

Actually, it might be a better idea to implement this is as some sort of shortcode override or alias, and use diy-oik.

[bobbingwide]

No longer required. I don't forget the shortcode name any more and there's now the github block.