applySpec returns null value as an object

[gaston-flores]

When using null as a value in the applySpec spec, it returns an empty object.

applySpec({
  aNull: null,
  aValue: 'hello'
})({})

Expected result:

{ aNull: null, aValue: 'hello' }

Actual result:

{ aNull: {}, aValue: 'hello' }

I believe the issue is this typeof, since the typeof of null is object

[nfantone]

@gaston-flores Good catch 👍🏼. #23 should address this.