Fix configuration for SonarCloud and add badge (#119)

Signed-off-by: Atsushi Neki <atsushin@fast.au.fujitsu.com>

.sonarcloud.properties

@@ -3,8 +3,8 @@
 #
 
 # Path to sources
-sonar.sources=app/**/*,client/**/*
-sonar.exclusions=**/e2e-test/**
+sonar.sources=.
+sonar.exclusions=**/e2e-test/**,**/test/**,docs/**/*,devenv/**/*,client/**/*.spec.js
 #sonar.inclusions=
 
 # Path to tests

README.md

@@ -10,6 +10,7 @@
 [![Documentation Status](https://readthedocs.org/projects/blockchain-explorer/badge/?version=master)](https://blockchain-explorer.readthedocs.io/en/master/?badge=master)
 [![Language grade: JavaScript](https://img.shields.io/lgtm/grade/javascript/g/hyperledger/blockchain-explorer.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/hyperledger/blockchain-explorer/context:javascript)
 [![Total alerts](https://img.shields.io/lgtm/alerts/g/hyperledger/blockchain-explorer.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/hyperledger/blockchain-explorer/alerts/)
+[![Quality Gate Status](https://sonarcloud.io/api/project_badges/measure?project=hyperledger_blockchain-explorer&metric=alert_status)](https://sonarcloud.io/dashboard?id=hyperledger_blockchain-explorer)
 <!-- badges -->
 
 Hyperledger Explorer is a simple, powerful, easy-to-use, well maintained, open source utility to browse activity on the underlying blockchain network. Users have the ability to configure and build Hyperledger Explorer on MacOS and Ubuntu.