Fix up generation of IPv6-ready configs for IPv6 testing

The testsuite uses a combination of:

• the ant script clustering-build.xml, with target build-clustering-udp
• the ant script common-targets.xml, with target ts.config-as.ip-with-multicast and
• the XSLT script changeIAddresses.xsl
  to set up IPv6 addresses for testing multi-node tests.

There are several problems:

• the XSLT script is broken and does not change the multicast addresses
• a number of multicast addresses are not receiving IPv6 defaults/overrides; in particular, we have the following required overrides:

UDP JGroups stack multicast requirements:
– socket-binding jgroups-udp: no IPv6 multicast address assigned, due to broken changeIPAddresses.xml
– socket-binding jgroups-diagnostics: no IPv6 multicast address assigned, due to no parameter passed in ts.config-as.ip-with-multicast

TCP JGroups stack multicast-requirements:
– socket-binding jgroups-mping: no IPv6 multicast address assigned, due to no parameter passed in ts.config-as.ip-with-multicast
– socket-binding jgroups-diagnostics: no IPv6 multicast address assigned, due to no parameter passed in ts.config-as.ip-with-multicast

mosdcluster multicast-requirements:
– socket-binding modcluster: no IPv6 multicast address assigned, due to no parameter passed in ts.config-as.ip-with-multicast

This results in server configurations which are not correctly configured for testing against IPv6 addresses.