* First stage of changing fields in NodeInfo.
Part of work related to NetworkMapService upgrade. Create slots for
multiple IP addresses and legalIdentities per node.
* NodeInfo stores HostAndPort.
Move information specific to messaging layer away from NodeInfo.
Only HostAndPort addresses are stored. Add peer name - peer handle
mapping to MockNetwork to reflect that change.
Fix bug in network simulator. It failed on cast when requesting signatures from notary, now it's not a SingleMessageRecipient but InMemoryMessagingNetwork.ServiceHandle.
* Fix how network visualiser displays node X500 names.
* Change locations of test nodes, so when used for explorer map visualisation not all of them are stacked one on another in London.
Change the legal name of parties to be an X500 name. This ensures that we aren't converting between
common names and X500 names in various places, eliminating substantial scope for error in the conversion
process. As a result, all node names must now be full X500 names, which has impact on most configurations.
