added DiffEqualityInvestigator
removed ChangeSet trait
renamed: DiffImpl->DeepDiff, FlatChangeSet->FlatDiff
deprecation annotations for Diff.hasDifference(path)
renamed test classes
fixes in FlatDiff api
formatted code + using diff factory instead of constructor
some DeepDiff direct constructions refactored to companion object invocations
more refs to DeepDiff changed to invocation on Diff companion
FlatDiff fixes
fixes in FlatDiff.without(..)