Disable reset/debug menus on boot

I've just updated https://github.com/espruino/Espruino/blob/master/README_Building.md#super-easy-github-method to be clearer about the zip.

maybe it wouldn't be hard for the firmware app to detect zip inside zip and just use the nested one?

I guess - although it'd need doing in the Bangle.js app loader and the Web IDE, so it's not a super quick thing to do.

There is also an argument that reflashing your Bangle.js firmware over the air to something you just made is potentially a dangerous thing to do - should it really be any easier than it is now (which is already pretty easy)?