0.2.1 breaks null and undefined states

[wopian]

0.2.1 switched to deep-assign which was deprecated 2 years ago (its essentially completely broken) and also doesn't handle null and undefined data types. merge-options should be used instead.

Uncaught TypeError: Cannot convert undefined or null to object (token)
    at assignKey (index.js?e77e:23)
    at assign (index.js?e77e:43)
    at assignKey (index.js?e77e:30)
    at assign (index.js?e77e:43)
    at deepAssign (index.js?e77e:64)
    at VuexPersistence.plugin (index.js?bff2:54)
    at eval (vuex.esm.js?358c:351)
    at Array.forEach (<anonymous>)
    at new Store (vuex.esm.js?358c:351)
    at eval (index.js?e3b1:63)

Where the state is:

const state = {
  token: null
}

Would also be a good idea to get a state with all 7 data types added to tests to prevent issues like this in the future

[championswimmer]

This is fixed now
Will cut a new release