CassandraTemplate: add nonstop and async methods
Merge branch 'master' of
https://github.com/SpringData/spring-data-cassandra.git

Conflicts:
	cassandra-base/src/main/java/org/springdata/cassandra/base/core/CassandraOperations.java
	cassandra-base/src/main/java/org/springdata/cassandra/base/core/CassandraTemplate.java
	cassandra-base/src/test/java/org/springdata/cassandra/base/test/integration/core/template/AsyncCassandraTemplateTest.java
	cassandra-base/src/test/java/org/springdata/cassandra/base/test/integration/core/template/CassandraTemplateTest.java
	cassandra-data/src/test/java/org/springdata/cassandra/data/test/integration/convert/CassandraDataConversionTests.java