IBM DB2 adapter

Zend Framework 2.1 now ships with an IBM DB2 adapter.

* Initial commit zendframework/zf2@823e727097e10de8373f36945fa9a3d35672f553

I've added a Statement Prototype class for IBM DB2 based on the Statement Prototypes for other drivers in BjyProfiler, and hooked it in to the Profiling Adapter class.