Adds alphanumeric support and v-model support

[TheSinding]

This adds support for using v-model instead of listening for on-complete. It also adds support for using alpha numeric input, where as before it was only numeric.

Then I did some code simplifying hope that is okay. Instead of using a boolean to add the last separator, it uses a CSS attribute ex. Removes the default value of the separator, as per your documentation

[TheSinding]

You can use it if you want :)

[bachdgvn]

Thanks for your contribution :D Love it. I'm going to review your pull this week.