Merge pull request #1 from codekaizen/master

Adding missing NHibernate.dll by removing and readding the nuget package.
Reimplemented ChainedFilter and EnumerableBasedDocIdSetIterator

ChainedFilter logic for ANDing multiple filters was incorrect.  Iterator
would throw exceptions.
Downloads NuGet.exe when it is missing.
Merge pull request #1 from codekaizen/master

Adding missing NHibernate.dll by removing and readding the nuget package.
Merge pull request #2 from CarlRaymond/master

Reimplemented ChainedFilter and EnumerableBasedDocIdSetIterator