Validation rule removes 0 from textfield.

[BrainOverfloW]

vue & vue-validator version

1.0.17, 2.0.0-beta.1

I've found a bug in the validation of fields containing the value 0. Once you add a validator rule to that field, the contents of the field disappears.

Reproduction Link: https://jsfiddle.net/g813xymd/

Steps to reproduce

Add v-validator to a textfield bound to a v-model with the value of 0

What is Expected?

The field should show 0

What is actually happening?

The field is empty

[BrainOverfloW]

Thanks for the quick fix.