Merge pull request #88 from PatrickDropbox/master

Refactor net2 connection pool to make it generic
Merge pull request #89 from PatrickDropbox/master

Implement a round robin resource pool
Merge pull request #90 from PatrickDropbox/master

add one more check for round robin pool
Merge pull request #91 from PatrickDropbox/master

modify round robin resource pool to support passing in existing pools during initialization.