aliasing component "props" names

[jossef]

What problem does this feature solve?

similar to angularjs directives, would like the ability to alias the names the component's parent uses to pass values

What does the proposed API look like?

component:

export default {
		name: "paging",
		props: {
			"count": {"name": "pagingCount", "type": Number}
		},

parent:

<paging v-bind:paging-count="itemsCount"></paging>

[posva]

Duplicate of #7943