a lot of improvements

1) added GeneralRepository - general implementation of abstract
RepositoryBase class
2) SharedRepository class - Represents the set of repositories.
3) RepositoryDispenser class - defines repository injected and generates
SharedRepositary instance.
4)IRepositary .AsEnumerable, .AsQueryable, .GetAllAndInclude
5) Testing: beefed up string queries, Include extension method, etc
Transactions support for test repository