Fixed reported line number for trailing comma error

The `no-comma-dangle` rule previously reported the ArrayExpression
or ObjectExpression node when finding a tailing comma. As a result
the rule would report the incorrect line for the error.

For example, in the code below line 1 would be reported as having
a trailing comma when line 3 is the true culprit!

var obj = {
	prop: "val",
	anotherProp: "va",
};

This fix reports the Property node in the case of an ObjectExpression
and whatever node type the array item is in the case of an
ArrayExpression.
Merge pull request #448 from iancmyers/tailing-comma-line-fix

Fixed reported line number for trailing comma error