Delete core/src/main/java/brooklyn/entity/basic/Destroy.java since deprecated since 0.4
* deletes the following files because they are deprecated since brooklyn 0.4
* delete core/src/main/java/brooklyn/entity/basic/PostStart.java
* delete core/src/main/java/brooklyn/entity/basic/PreStart.java
* delete core/src/main/java/brooklyn/entity/basic/PreStop.java
deletes core/src/main/java/brooklyn/entity/basic/Create.java since deprecated since brooklyn 0.4
Merge pull request #738 from pveentjer/delete-Create

deletes core/src/main/java/brooklyn/entity/basic/Create.java since depre...
Merge pull request #737 from pveentjer/deletePrePostMethods

* deletes the following files because they are deprecated since brooklyn...
deletes some of the deprectated threading code since they are deprecated since 0.4
* deleted:    core/src/main/java/brooklyn/util/task/SingleThreadedExecution.groovy
* deleted:    core/src/test/java/brooklyn/util/task/SynchronizedExecutionTest.groovy
Merge pull request #736 from pveentjer/delete-Destroy

Delete core/src/main/java/brooklyn/entity/basic/Destroy.java since depre...
Merge pull request #739 from pveentjer/deleteDeprecatedBrooklynUtilTask

deletes some of the deprectated threading code since they are deprecated...
Delete Entity.getOwner/setOwnedChildren etc
Merge pull request #741 from aledsage/delete/deprecated-Entity.owner

Delete Entity.getOwner/setOwnedChildren etc