Merge pull request #78 from ialekseev/master

Adding XML comments to configuration methods + slight refactoring
Merge pull request #79 from ialekseev/master

Updating wiki project
Merge pull request #80 from ialekseev/master

Adding new method in CodeContracts Require + using it in few places
Adding UnitOfWork setting to allow throwing exception if nested UnitOfWork detected
Updating Nuget specs + Sample project