test(connector-go-ethereum-socketio): add functional test, bug fix

- Add functional test of all functions from go-ethereum-socketio validator.
- Refactor go-ethereum validator to allow importing as a module, to simplify the functional test.
- Fix sendRawTransaction to work with Verifier protocol.
  It couldn't be reached by any client library until now, so I consider this as "private" interface.
- Add common web3 client object in openethereum test ledger helper class.
- Add few new functions to ethereum test ledger helper class:
  newEthPersonalAccount, transferAssetFromCoinbase, deployContract.

Depends on hyperledger-cacti#2051
Depends on hyperledger-cacti#2047

Closes: hyperledger-cacti#2052

Signed-off-by: Michal Bajer <michal.bajer@fujitsu.com>

packages/cactus-plugin-ledger-connector-go-ethereum-socketio/package.json

@@ -2,6 +2,9 @@
   "name": "@hyperledger/cactus-plugin-ledger-connector-go-ethereum-socketio",
   "version": "1.0.0",
   "license": "Apache-2.0",
+  "main": "dist/common/core/bin/www.js",
+  "module": "dist/common/core/bin/www.js",
+  "types": "dist/common/core/bin/www.d.ts",
   "scripts": {
     "start": "cd ./dist && node common/core/bin/www.js",
     "debug": "nodemon --inspect ./dist/common/core/bin/www.js",
@@ -28,6 +31,7 @@
     "web3": "0.20.7"
   },
   "devDependencies": {
+    "@hyperledger/cactus-api-client": "1.0.0",
     "@types/config": "0.0.41"
   }
 }