Signature cleanup (#1921)

* Address renamed to H160 at bigint library level

* moved uint specific test from util to bigint library

* naming

* unifing hashes in progress

* unifing hashes

* cleanup redundant unwraps in tests

* Removing util/crypto in progress.

* fixed compiling

* signature cleanup in progress

* new module - ethcrypto used by ethstore and ethcore-network

* fixed compiling

* fixed compiling

* fixed merge