Trivial XML syntax error fixed.

Committing trivial fix directly to master. Minor XML syntax error - no
space between two attributes. Seems that most XML parsers didn't mind
this but a strict parser (e.g. xpath command on OSX) rejects it.
EC2 CentOS 6.3 test: openIptables=true

- The AMI has iptables locked down; need to open iptables for the
  jclouds “open ports”. Otherwise things like JBoss7 live test fails.
Fix NodeJs live tests: don’t assert REQUEST_COUNT

- attributes like REQUEST_COUNT are not set for NodeJs, so don’t 
  assert that they are non-null
TaskFinalizer: add TODO about logging
fix for TomcatServerSoftlayerLiveTest
[maven-release-plugin] prepare branch 0.7.0-M2-incubating
[maven-release-plugin] prepare for next development iteration
This closes #306

* github/pr/306:
  fix for TomcatServerSoftlayerLiveTest
entity.getAllAttributes() return everything

- Even if the AttributeSensor is unknown for a given key name, still
  return it.
- There’s a race where persister thread calls getAllAttributes() at
  same time as new attribute type is being added to entityType.
  Previously the sensor was not returned, so was not persisted.
RebindTestFixture: support for dumping mementoDir

- Create a mementoDirBackup field, in case wants to be used by
  sub-classes.
- Adds dumpMementoDir(File dir)
More logging for failing BindDnsServerIntegrationTest

- Fails non-deterministically on jenkins; can’t reproduce locally.
  Therefore adding logging to dump out a copy of the persistence dir,
  as it was at the point of rebind.
- Also terminates the old management context.
This closes #308
Adds Listener support for usage/metering info
TypeCoercions: recursively unpack for List<T>

- e.g. if given “1,2” for type List<Integer>, then first pass will
  coerce to List.of(“1”, “2”), and second pass will coerce to
  List.of(1,2)
Read UsageListeners from config in brooklyn.properties
This closes #310
make heartbeat timeout (to trigger failover) and poll period configurable from brooklyn.properties
support multiple instances of the same osgi symbolic-name:version
clean up copyPersistedState code

move shared code to new `BrooklynPersistenceUtils`,
make a new `LocationWithPersistenceStore.newPersistenceObjectStore` interface,
and add documentation for `copy-state` command
better docs for persistence, and misc comments elsewhere