Add IDE settings to select RSTDISBL fuse setting (or, at least, stop blatting the setting when we write)

[leepgent]

I use a high-voltage programmer to program the tn13 but MicroCore's fuse settings keep overwriting the fuse. This MR allows the user to select the fuse setting (at most) and stops overwriting the fuse setting at least.

Not sure about the wording of the menu items, it needs to be alarming but not too long!