Introduce CKEDITOR.tools.object.merge function

[mlewand]

Are you reporting a feature request or a bug?

New feature

Provide detailed reproduction steps (if any)

We need a function to recursively merge objects.

This function should take 2 params obj1, obj2 and return the object that is a result of merging the two. Keep in mind that neither obj1 nor obj2 should be modified by this function (add a TC for that).

If the same primitive value is available in obj1 and obj2, the value from obj2 should be used.

This function should land in CKEDITOR.tools.object namespace, as a merge function.

If possible function may do a feature detection and use Object.assign.

Examples

{
	one: 1,
	conflicted: 10,
	obj: {
		nested1: 1
	}
}

{
	two: 2,
	conflicted: 20,
	obj: {
		nested2: 2
	}
}

Should result with the following object:

{
	one: 1,
	two: 2,
	conflicted: 20,
	obj: {
		nested1: 1,
		nested2: 2
	}
}