See how this works.I have done patch between two branches.

Please check that handlers stuff. I am not sure how to test it, and am
not sure I get those correct; especially tramp-crypt.

I am using a regular expression from Dired+ by Drew in two places. I
have mention it the comment in ert tests, but don't know how to mention
it in the example in manual. Maybe remove example, or maybe it can stay
without creds?

I also discovered that I wasn't covered with FIXNUM all the way; thought
it was unsigned int so -1 would be converted into ffffffff, which
would just yeild all results. Seems like fixnum is not what I thought so I
have added test for <=0 which return nil.

Ert test are mostly foxused on new argument. I haven't found something
related to dired in test/src so I have created dired-tests.el. If it
shoudl be in some other place I can rename it.

Best regards
/a