Update for new 2.0 driver

[iamgurdip]

Please update or create a new version based on the new 2.0 driver.

[runxc1]

I have a pull request to update to mongodb 2.0. So far it is working on my machine though you will need to clear out the collection used to store errors as the serialization of the error is changed. See #16

[sharma-bhavesh]

so far seems to be working, as you mentioned we had to drop the collection but from thereon a smooth sail. Thank you @runxc1 (Bret)