Clear button support

[ehartford]

On Microsoft Sculpt numpad there's a Clear button Could you please make Nimble clear the calculation when that is pressed?

[ehartford]

would also be cool to have an option during install, to set Nimble as the default Calculator so that the calculator button would open Nimble

[jmshal]

That would be pretty cool to support. We'll consider the feature request, for sure :)

[soops]

I'll try this soon.