[2.0.0] Query builder's constructor update

I spent some time to make constructor up-to-date in version 2.0.

PS. I don't even know how to build it straight from changed zep souce(phalcon dir)? neither how to run unit test with usage of this particular version?

PS. PS. README.md doesn't say anything about dev builds(normally it was ./install in /ext dir but now it's different). Maybe it would be worth to create a README.dev.md to help people from 'outside' to clone, do their bit, unit test and create pull requests.

Thanks in advance,

Kamil