towards generic method polling and reposito;y; config settings to
filterevents/methods by account address; refactoring some stuff out of
repo and into converter; remove fetcher and instead call
blockchain's FetchContractData directly; finishing tests
* Separate Repository into multiple Repositories
* Use struct scan for transactions
* Use struct scan for blocks
* Remove unused block repo methods
* Update naming
* Rename / Cleanup repository related fields
* Conversion between Geth Receipt and core.Receipt
* Add receipt to DB
* Insert receipts with transactions
* Update Travis CI to use dep for dependencies