RE: New repository created for Hive Engine source code

For similar reasons rebranding was done in Hive code for HF24, but there were still some leftovers. Now HF26 changes all last uses of SPS in hived into DHF (not only internally but also in names of virtual operations) and you can sign transaction that expresses all its assets with NAI when serialized to binary (the form that is signed) - legacy form is still ok at least until HF27, but it has that problematic "STEEM" or "SBD" as names of assets (again, when you look at binary form), so it should be avoided after HF26 (as a bonus NAI form is slightly smaller than legacy and as such is also slightly cheaper in terms of RC).