Added object to cross over empty lines

[D4KU]

I added a text-object to include adjacent simple line comments only separated by an empty or white-space-filled line.
So if > marks the current cursor line, comments b to d are matched.

  // a
  if (false)
     return;
  // b

  // c
> // d

Because this new object is greedier than the others I figured it would make sense to call it aC, and renamed the existing aC to iC.