`and` returns non-boolean value rather than converting it (which breaks default value logic)

[emattias]

The and helper returns the value as it is if its falsy (rather than converting it to a boolean first) here: https://github.com/jmurphyau/ember-truth-helpers/blob/master/packages/ember-truth-helpers/src/helpers/and.ts#L33

This results in some unexpected behavior, see twiddle

Suggestion

Can we change that line to:

return truthConvert(params[i]);

or

return !!params[i];

So that and returns false rather than undefined when it gets undefined. That would result in a more expected behavior IMO.