Migrate usages of Truth's Subject.is(Object) to isEqualTo(Object). The former is being removed.

Tested:
TAP --sample for global presubmit queue
[]
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72339878
Remove references to org.truth0. The new package is com.google.common.truth.

Tested:
TAP --sample for global presubmit queue
[]
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72422620
Migrate from Truth.ASSERT to Truth.assert_() or Truth.assertThat().
Tested:
TAP --sample for global presubmit queue
[]
-------------
Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72556077
Hide Truth.ASSERT and fix up the remaining callers.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72746146
Remove the EqualityScanner as it was replaced by the TreeDiffer.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73927548
Close the streams opened when testing resources.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73929814
Fix NPE thrown in parallelScan() of TreeDiffer.

Previously, parallelScan() failed when passed two null iterable values. This CL
fixes this by performing the proper null pointer check before attempting to
dereference in order to access the parameter's iterator() method.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74252905
Expand compile-testing to be able to verify that the original source files compile to the same tree as another set of source files.  This enables testing of generated code that is not generated by an annotation processor.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74873601
Automated g4 rollback of changelist 74873601.

*** Reason for rollback ***

Mysterious classloader errors.

*** Original change description ***

Expand compile-testing to be able to verify that the original source files compile to the same tree as another set of source files.  This enables testing of generated code that is not generated by an annotation processor.

***
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74883754
Merge pull request #53 from google/moe_writing_branch_from_8867a5afd90e3e12c01a964b073fd8558e029aa9

Updates from Google internal repository, mostly cleanup.