[bitshares/bitshares-core] unsigned_int unpacking (#1267)

Resolves #993

TODO:
* [x] remove signed_int references from core because it’s broken
* [ ] bump fc after merging https://github.com/bitshares/bitshares-fc/pull/64
You can view, comment on, or merge this pull request online at:

https://github.com/bitshares/bitshares-core/pull/1267

— Commit Summary —

* Removed broken signed_int

— File Changes —

M libraries/chain/include/graphene/chain/protocol/types.hpp (1)
M libraries/db/include/graphene/db/object_id.hpp (1)
M programs/js_operation_serializer/main.cpp (1)

— Patch Links —

https://github.com/bitshares/bitshares-core/pull/1267.patch
https://github.com/bitshares/bitshares-core/pull/1267.diff