Reimplement ThrowingConsumerTest so that Callables return an integer

For this, use an AtomicInteger. In @BeforeMethod, reset it to 0 so that we know
that it has been set on stubbing .doAccept().
Reimplement ThrowingBiConsumerTest so that Callables return an integer

Same as ThrowingConsumerTest.
Reimplement ThrowingDoubleConsumerTest so that Callables return an integer

Same as ThrowingConsumerTest.
Reimplement ThrowingIntConsumerTest so that Callables return an integer

Same as ThrowingConsumerTest.
Refactored Obj*Consumer tests
Merge pull request #8 from Vincentyification/topic/testrefactor

Refactored Obj*Consumer tests
Finish consumer conversion to new tests
Rename instance getting methods
Refactoring: pass results to the constructor
Refactoring: rename some methods
Tests: get rid of the Runnable

It is now unused. Transform the verify* exception methods to take a Callable as
an argument instead.
New base interface for tests
Test refactor: Comparator
Import optimization
Convert all Consumer tests to the new test code
Convert all {Double,Long,Int}*Functions to new tests
Convert all *Operators to new tests
Convert the last remaining Functions to the new tests
Convert all Predicates to the new tests
Convert all Suppliers to the new tests