updates to use jclouds 1.5 w/t deprecated code
proposal for #430
Shane's comment addressed
Added webServer.stop() in a finally block to tests
Cassandra entity and initial Cassandra Cluster entity
Changes from review
Added Cassandra Live tests for Rackspace
Add agent to start RMI server for JMX
Rename CassandraServer to CassandraNode
Update CassandraCluster live test
Changes from review comments
Use CassandraCluster in demo application
Updated cluster entity factory and seed/token management for nodes and modified cluster live test to use Astyanax API
Removes SSH keys
Use brooklyn.properties and a BasicLocationRegistry to obtain a JcloudsLocatrion

Conflicts:
	software/messaging/src/test/java/brooklyn/entity/messaging/activemq/ActiveMQEc2LiveTest.groovy
	software/webapp/src/test/java/brooklyn/entity/proxy/nginx/NginxAmazonTest.groovy
	software/webapp/src/test/java/brooklyn/entity/webapp/WebAppLiveIntegrationTest.groovy
Use non-deprecated location resolver
Conflicts:
	core/src/main/java/brooklyn/entity/basic/Entities.java
	core/src/main/java/brooklyn/management/internal/LocalManagementContext.java
	software/webapp/src/test/java/brooklyn/entity/proxy/nginx/NginxAmazonTest.groovy
Fix Jclouds tests to use non-deprecated code
Further work fixing JcloudsLocation based tests
add support for allocatePTY flag when used with SSH CLI, and corresponding integration tests
misc test fixes