Add Gee.Lazy class (call-by-need)
Add Iterator.unfold function
Add Iterator.concat function
Add Iterator.stream method based on stream fusion
Add Iterator.map method
Add Iterator.scan method
Export the function part of interface into Traversable
Add Gee.Traversable<G> requirement to Gee.Iterable<G>
Preserve laziness in Stream
Fix Traversable<G>.stream in ReadOnlyCollection
Add Traversable<G>.filter method
Update documentation
Fix ordering of prerequests
Allow to install libgee 0.6 and 0.8 in parallel
Add filter tests
Fix default Traversable.stream implementation for Iterator<G>

The implementation assumed in unfolding function that the stream  some
value - however it might not be the case.
Add Traversable.chop function
Fix standard functions for nullable types
Release 0.7.0
Post-release version bump