mounting options: global

[lmiller1990]

move plugins and mixins to global

[dobromir-hristov]

Should we also add component, directive and config.globalProperties?
With those added, we allow them to mimic their global app config fully.

interface MountingOptions<Props> {
  ...
  global?: {
    plugins?: Plugin[]
    mixins?: ComponentOptions[]
    directives: Directive[]
    components: Component[]
  },
}

[lmiller1990]

Sure, makes sense!