Fixed a problem with insert_bulk 

php 5.4.16
Correct use of insert_bulk ($a = array(array("",""), array("",""));) causes this error:
'Problem "Strict standards: Only variables should be passed by reference"'
The solution is based on comments on stackoverflow (http://stackoverflow.com/q/2354609)
Merge pull request #2 from etb09/patch-2

Fixed a problem with insert_bulk