Add support for banning problematic ciphers for Jetty SSL connectors

An earlier patch added support for banning ciphers through the JGlobus
library.  The same problem exists for the connectors supplied with
Jetty, which are used in the WebDAV/HTTP door and the webadmin.

This patch adds support for banning problematic ciphers for
these services.

Target: master
Request: 2.6
Signed-off-by: Paul Millar <paul.millar@desy.de>
Acked-by: Gerd Behrmann <behrmann@nordu.net>
Patch: http://rb.dcache.org/r/5614/
Require-notes: yes
Require-book: no
(cherry picked from commit d22ef811e7a3bd8f15093ed1fc199eda6b18b025)

Conflicts:
	modules/dcache/src/main/java/org/dcache/services/httpd/HttpServiceCell.java
Merge pull request #85 from gbehrmann/fix/2.2-sha2/rb5614

Add support for banning problematic ciphers for Jetty SSL connectors