No options submitted to `install` in vue 3.0.5

[PHPGuus]

Hi there,

Using vue3.0.5 and simple-vue-validator0.2.0, I simply do:

import VueSimpleValidator from 'vue-simple-validator';

createApp(App)
    .use(VueSimpleValidator)

in my main.js, and I get the following error on the console:
Cannot read property 'errorMessages' of undefined

It appears that typeof options.errorMessages does not work as expected when options is undefined.

I'll propose a PR for this issue in a few minutes.

Best regards,
Guus