#1236 sort the Violations Overview by Violation Type

[Noel Grandin]

Please add the ability to sort the Violations Overview by Violation Type.
i.e. so that I can see all of the files in a given project that are affected by a given Violation.

My use-case is that I like to fix all of the violations of the same type in one pass, because it is more efficient that way.

Thanks.