+ refactoring iterators
+ move iterators to \Qmaker\Iterators namespace
+ added Dictionary, HashSet, OrderedDictionary, Lookup classes
! not working commit
tests for CallbackIterator, CallbackFilterIterator, DistinctIterator, ExceptIterator, IntersectIterator, ProductIterator, ProjectionIterator, SkipIterator, TakeIterator
tests for GroupingIterator
tests for JoinIterator, IndexIterator
tests for OuterJoinIterator
rename keys() method in ProductIterator to key()
move Qmaker from lib to the root folder
add IEnumerable
implement Operation\Generation in IEnumerable