Type safe objects for each component

[g105b]

Rather than returning an array for everything, return an object of the appropriate type.

For example:

UpdateQuery::set():AssignmentList

class UpdateStudentName extends UpdateQuery {
  public function set():AssignmentList {
    return new AssignmentList(
      "name",
      new Assignment("updatedAt", new NowDate()),
    );
  }
}