Issue 86

Please review these bulk compute test cases, i have updated them according to java doc. Let me know what changes are needed. Thanks
This test is not targeting the contract. The only part of the javadoc that seems related to this test is "If the entry's value is null, the mapping will be removed from the store." 
However it is not what is tested here.
Besides, other assertions/operations are unnecessary to test that part of the contract (if that's the intent of this test)