Fix DynamicCluster check for initialSize reached

- Got error "failed to get to initial size of 2; size is 2"
- Most likely reasons looks like object equality on Integer.
  But not sure why that hasn't popped up before if that is the cause,
  rather than it being a race on startup.
Redner BrooklyNode.WEB_CONSOLE_URI as a link in web-console
Add BrooklynNode.PORT_MAPPER

- For if working with DNAT, the port we ask for might not be the same
  as the port we use in the brooklyn web-console.
Expose BindDnsServer.getAddressMappings as effector
BindDnsServer: fix comment format in domain.zone

- comments are semi-colon rather than c-style
  (at least on the CentOS 6.4 VM I'm testing with!)
BindDnsServer: don't extend JavaSoftwareProcessSshDriver

- instead extend AbstractSoftwareProcessSshDriver because this is
  not using java
BindDnsServer: fix race for adding existing entities
Fix BindDnsServer.removed(Entity) for when loc unknown

- on entity stopping, getLocations() might return empty - because
  they've just been cleared.
- therefore do a reverse lookup of our map instead to find the node
  being removed.
- TODO: make the reverse-lookup more efficient so can scale
Merge pull request #4 from aledsage/bind-entity-fork-grkvlt

Minor fixes (during brooklyn-cdh vcloud work)