[sil_euro_latin] don't auto-switch to default layer when on numeric layer

[ermshiperete]

In German the comma is used as decimal separator. When on the numeric layer and typing digits followed by a comma, the keyboard switches back to the default layer. If you type a period instead, it stays on the numeric layer.

Looking at the other keys on the numerical layer, they are all related to numbers and math, and so I think it would make more sense to disable automatic layer switching for the numeric layer. Typing any key on the numerical layer stays on the numerical layer. To go back to the default layer you press the layer button.