Add integration with SonarCloud

.travis.yml

@@ -1,5 +1,10 @@
 language: go
 sudo: false
+addons:
+  sonarcloud:
+    organization: "akamensky"
+    token:
+      secure: "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"
 go:
   - "1.11"
   - "1.12"
@@ -10,3 +15,4 @@ before_install:
 script:
   - go test -v .
   - $GOPATH/bin/goveralls -service=travis-ci
+  - sonar-scanner

sonar-project.properties

@@ -0,0 +1,16 @@
+sonar.projectKey=akamensky_argparse
+# this is the name and version displayed in the SonarCloud UI.
+sonar.projectName=argparse
+sonar.projectVersion=1.0
+
+# Path is relative to the sonar-project.properties file. Replace "\" by "/" on Windows.
+# This property is optional if sonar.modules is set.
+sonar.sources=.
+sonar.exclusions=examples/**
+
+# Path to tests
+sonar.tests=.
+sonar.test.exclusions=examples/**
+
+# Source encoding
+sonar.sourceEncoding=UTF-8