Refactor HadoopCredentialConfiguration in preparation for adding StormCredentialConfiguration.
	Change on 2014/07/18 by jimmc <jimmc@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71461891
Reduce integration test runtime to 2m30s (from 15+) when run with []. TAP is now on the order of 7 minutes for both hadoop and hadoop2 (since they can both cause the other to be slower due to quota and backoff)

Introduces the idea of TestBucketScope which allows multiple tests to share a
single bucket and cleanup test resources when going out of scope.

When using a SharedBucketScope, which shares a single bucket amongst multiple
tests, prevent the test from using list methods that could bring in objects
from other tests.
	Change on 2014/07/21 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71616106
Add tests and EntriesBuilder for EntriesCredentialConfiguration.
	Change on 2014/07/22 by jimmc <jimmc@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71704344
Remove ExceptionUtil from GCSIO tests and replace with ExpectedException based tests
	Change on 2014/07/24 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71877574
Remove ExceptionUtil from GHFS tests and replace with tests based on ExpectedException
	Change on 2014/07/24 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71877897
Remove ExceptionUtil.java
	Change on 2014/07/24 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71878413
Log 410 and 503 request URLs as well as those that generate IOExceptions.
	Change on 2014/07/24 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=71879001
Pair is not in Guava, remove it from tests.
	Change on 2014/07/30 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72277721
Make Hadoop 2.4.1 the hadoop2 default
	Change on 2014/07/31 by pclay <pclay@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72334006
Update GCS CHANGES.txt for build changes
	Change on 2014/07/31 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72355997
deprecate system bucket and gsg
	Change on 2014/08/01 by pclay <pclay@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72446191
Add the extra voodoo magic necessary for EntriesCredentialConfiguration.Builder
to really be a generalized builder, by specifying the "builder of what" param
as the second template param. This is necessary for GcsFsShell to work again.
	Change on 2014/08/06 by dhuo <dhuo@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72759398
update CHANGES.txt dates
	Change on 2014/08/07 by pclay <pclay@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72841885
update pom.xml
	Change on 2014/08/08 by pclay <pclay@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72914105
For gcsio tests, add a gcs.log that sponge can find and record.

This should (hopefully) help us collect logs from TAP failures.

Example run:
https://sponge.[]/target?tab=Test%20Outputs&target=//javatests/com/google/cloud/hadoop/gcsio:UnitTests&id=ee282441-f034-40b1-b70d-d6676e110f57&sortBy=STATUS&show=ALL&searchFor=user:angusdavis
	Change on 2014/08/08 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72914535
Fix debug logging in OperationWithRetry. The %s for the exception is implied.
	Change on 2014/08/08 by angusdavis <angusdavis@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72916752