added Test for multiple m-1-m childs in multiple states (added, modified)
added fix for recursion of m-1-m childs, avoid childs in trackingstate Modified to run in recursion path for added

Increased test coverage:

Updated Apply_Changes_Should_Mark_Unchanged_Order_Unchanged_Customer_With_Addresses_Mutliple_Added_And_Modified (succeeded)

Added Apply_Changes_Should_Mark_Unchanged_Order_Unchanged_Customer_With_Addresses_Multiple_Added_And_Modified_Deleted (succeeded)
Cleaned up this test:
Apply_Changes_Should_Mark_Unchanged_Order_Unchanged_Customer_With_Addresses_Mutliple_Added_And_Modified (succeeded)

Added this test:
Apply_Changes_Should_Mark_Unchanged_Order_Unchanged_Customer_With_Addresses_Multiple_Added_And_Modified_Deleted (succeeded)
Added test:
Apply_Changes_Should_Mark_Unchanged_Order_Unchanged_Customer_With_Addresses_Multiple_Added_And_Unchanged

Fails with InvalidOperationException:
Attaching an entity of type 'TrackableEntities.EF.Tests.NorthwindModels.CustomerAddress' failed because another entity of the same type already has the same primary key value.
Fixed failing test:
Apply_Changes_Should_Mark_Unchanged_Order_Unchanged_Customer_With_Addresses_Multiple_Added_And_Unchanged

Added DeContextExtensions.ApplyChangesOnCollectionProperties method to process Added items before others.