* update transformer to able to recheck headers
* put cap on rechecking header
* integration test for recheck headers
* use enum for recheck headers param; make recheck cap configurable
* update integration tests with new test config
* update omni pkg with new recheck header column type
* update migration with new migration tool and final tweaks needed to accommodate changes in omni pkg
- Continuously parse storage diffs CSV data to read Pit contract state
- Convert ilks in database to raw bytes32 value for use in generating
storage keys dynamically
- Persist storage diffs with block number and hash for validation
* Upgrade geth from 1.8.15 to 1.8.18
* Update vat_tune to use shared repository methods
* Query blockchain by block hash instead of block number range
* Remove hash validation from repositories
* Fix vow flog integration test
* Update README Travis build sticker
* Update constants formatting per go fmt
* Update EthPublicKeyParser.ParsePublicKey to use discv5.PubkeyID method
* Address PR comments
* Use shared repository tests for deal
* Small updates to repo tests
* Use shared repository test examples for dent
* Use shared repository test examples for drip_drip
* Use shared repository test examples for drip_file_ilk
* Use shared repository test examples for drip_file_repo
* Use shared repository test examples for drip_file_vow
* Update formatting
* Move chop lump transformer test to a generic log_note_transformer_test
* Add test cases to transformer test
- cat file flip
- cat file pit vow
- deal
- dent
* Move transformer tests over to transformer factor test file
- drip drip
- drip file ilk/repo/vow
- pit file deb ceiling/ilk/stability fee
- price feeds
* Move LogNoteTransformer test into factory package and remove log specific transformer tests
* Move Transformer test into factory package and remove log event specific transformer tests
* Respond to PR comments
* Use transformer factory for Bite
- introduces separate transformer factory for non-LogNote events
- converter includes `ToEntities` for events defined via ABI
* Updates after rebasing with staging
