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
I understand those assertions as testing the line "Every missing entry in the returned {@link Iterable} will be ignored and the store will be left untouched for that key,".
If that's the case, that would make sense that it is asserted before the call to the method that those keys would also contains null values.

Actually, it seems that it would even be clearer to get the values in the store before the call to the method and assert here that the current values are the same as before (instead of asserting null).