Validate comma spacing in arrays

[aik099]

We need to validate that for cases when:

1. there are several elements of array placed in a single line (not exactly inline array)
2. not for last element in a row

we need to ensure that a space is present after comma.

Valid:

$something = array(1 => 'aa', 'bb' => 'cc');

Invalid:

$something = array(1 => 'aa','bb' => 'cc');

The ArrayDeclaration sniff from Squiz coding standard has some good code for checking what we need, but it only applies to inline arrays.

[aik099]

Closing as special case of #54, which obviously more general case for that problem.