Checker status

[Gunnar Hjalmarsson <mailbox@gunnar.cc>]

As a result of the first tests of the Ringlink checker, I have
implemented a couple of features that will make it easier both to use it
and to understand some of the failures.
- Now it's possible to check just a portion of the active sites in a
  ring.
- The result page states which sites have been checked.
- The actual server responses for the failed sites can be viewed
  on the screen.
I have also made a couple of minor improvements of the code in order to
increase the checker's ability to evaluate whether the checked links are
acceptable or not. My aim is that all links that work with a browser
shall pass.
The following files have been changed:
        admin.pl
        ringadmin.pl
        ring.pm
So far I think we can conclude that no sites pass which obviously should
have failed. Please let me know if you find examples of exceptions from
this rule.
The main problem, which still remains, is the checker's insufficient
ability to "talk" to the servers, resulting in the server responses all
too often being something else than the HTML code which appears when a
URL is called from a browser. I still would appreciate very much if
somebody could help me to improve the code in this respect.
/ Gunnar