Create some pure validation functions

https://github.com/FACG2/Blog/blob/master/public/js/sign_up.js

Eg.
```
var validationFuncs = {
  email: (value) => value.match(/..../)
}
```


here aswell you can do this...
https://github.com/FACG2/Blog/blob/master/src/handlers/post.js#L54