Using assertj assertions

testng assertions have been replaced with assertj
assertions.
Use assertj extraction feature to shorten test
JCLOUDS-457: uploadPart return type fix

The uploadPart method now returns HashCode instead
of String.
JCLOUDS-457: Test groups and improvements

Test groups have been added. Also, the live tests were
refactored to reduce the number of RPCs.
JCLOUDS-457: Add JobStatus enum

Now the job status is stored as an enum instead of
a String. This is useful when comparing the status to
check if a job is completed, failed or still in progress.
JCLOUDS-457: BlobStore Skeleton

The Amazon Glacier BlobStore skeleton has been added.
JCLOUDS-457: Fix complete MPU archive size

The completeMultipartUpload operation is taking the archive size
parameter in MB but it should be bytes.
JCLOUDS-457: BlobStore MultiPartUpload strategy

The code related to the MultiPartUpload strategy has been added.
MultiPart uploads use an upload strategy (e.g. sequential vs parallel)
and also a slicing strategy to split the payload in different parts.
JCLOUDS-457: Long live tests

The long live tests have been added. These tests takes several
hours and will leave traces in your AWS account.
JCLOUDS-457: List containers and remove blob

List containers and remove blob operations have
been added.
JCLOUDS-457: Add polling strategy

The polling strategy interface for job operations
and a simple implementation class have been added.
This implementation waits an initial time and then
polls at regular intervals.
JCLOUDS-457: Add getBlob operation

Now the BlobStore abstraction supports the getBlob Operation
JCLOUDS-457: Add list operation

Now the BlobStore abstraction supports the list Operation
JCLOUDS-457: Add blobExists and blobMetadata

Now the BlobStore abstraction supports the blobExists and the
blobMetadata operations.
JCLOUDS-457: Add Clear vault strategy

Added a proper implementation to the Clear vault strategy
JCLOUDS-457: Fix deleteContainer

The ClearVaultStrategy now ignores ResourceNotFound exceptions.

deleteContainer now tries to delete the vault first to avoid long waits.
If the delete request fails, retries it every 24 hours.
JCLOUDS-457: Small fixes and documentation

Now the BlobStore and the strategy implementations are annotated with @Singleton.

Added a small documentation to the blobstore classes.