* Support cast vote by signature in ZrxTreasury
* Address comments and fix existing tests
* test that doesnt work
* test file format
* updates
* address some of the comments
* Remove unused const
* get rid of vote_factory
* unit test for castVoteBySignature p1
* unit test for castVoteBySignature p2
* Add version to domain, and one more test
* unit test for castVoteBySignature p3
* unit test for castVoteBySignature p4
* bump utils version
* remove debug code
* address some comments
* address more pr comments
* move Vote class to protocol-utils
* Address pr comments and update changelogs