Added task execution framework
Migrated graph over to new task executor
Added events and task cleanup
Converted tasks to ForkJoin tasks to allow for parallel execution.
Added tests for the log entry iterator
Beginnings of a rebuildable index implementation and associated test.
Finished testing of the EntityVersionCleanupTask
Revert "Converted tasks to ForkJoin tasks to allow for parallel execution."

This reverts commit dc3f448c946219c44e3dbfadb294fea0b8048343.

The ForkJoinPool does not have the following characteristics

Ability to name a pool
Ability to set queue size for rejection

As a result, it is not well suited for our asynchronous I/O tasks, and I'm moving back to ExecutorService

Conflicts:
	stack/corepersistence/collection/src/main/java/org/apache/usergrid/persistence/collection/impl/EntityVersionCleanupTask.java
	stack/corepersistence/common/src/main/java/org/apache/usergrid/persistence/core/task/ImmediateTask.java
	stack/corepersistence/common/src/main/java/org/apache/usergrid/persistence/core/task/NamedTaskExecutorImpl.java
	stack/corepersistence/common/src/main/java/org/apache/usergrid/persistence/core/task/Task.java
	stack/corepersistence/common/src/main/java/org/apache/usergrid/persistence/core/task/TaskExecutor.java
	stack/corepersistence/common/src/test/java/org/apache/usergrid/persistence/core/task/NamedTaskExecutorImplTest.java
	stack/corepersistence/graph/src/main/java/org/apache/usergrid/persistence/graph/serialization/impl/shard/ShardGroupCompaction.java
	stack/corepersistence/graph/src/main/java/org/apache/usergrid/persistence/graph/serialization/impl/shard/impl/ShardGroupCompactionImpl.java
Finished updating back to executor pool
Merge branch 'two-dot-o' into eventsystem
Beginning of some new migration methods.
Removed stress tests that should not be part of the build
Resolved conflicts when guice modules are integrated
Merge branch 'two-dot-o' into eventsystem
more logging
change to info logging
Added additional logging and a short circuit test
Merge branch 'two-dot-o' of https://git-wip-us.apache.org/repos/asf/incubator-usergrid into two-dot-o
Added guard for extending UUID on failed transactions beyond the max of the queue.
Fix for partial update error