Visual Studio comment/uncomment shortcut keys in config files

Visual studio's shortcut keys for commenting (Ctrl-K, C) and uncommenting (Ctrl-K, U) and very handy for blocks of code or even singles lines if your cursor is not at the start of the line.

Something interesting though is that these shortcuts also work within the config files putting <-- and --> at the start and end of the line(s) as required (or removing them if you're uncommenting).

Very handy if your development config files contain multiple connection strings etc.