add coverage badge

Author: rinick

.nycrc

@@ -5,7 +5,9 @@
   ],
   "include": [
     "ts/src/**/*",
-    "js/src/**/*"
+    "js/src/**/*",
+    "ts/test/**/*",
+    "js/test/**/*"
   ],
   "exclude": [
     "**/*.d.ts",

README.md

@@ -2,3 +2,4 @@
 typescript/javascript sdk for DSA protocol
 
 <a href='https://travis-ci.org/IOT-DSA/sdk-dslink-ts'><img src="https://travis-ci.org/IOT-DSA/sdk-dslink-ts.svg?branch=master" title="travis-ci"></a>
+<a href='https://coveralls.io/github/IOT-DSA/sdk-dslink-ts'><img src='https://coveralls.io/repos/github/IOT-DSA/sdk-dslink-ts/badge.svg?branch=master&service=github' title="coveralls"/></a>

ts/test/test_util.ts

@@ -25,4 +25,4 @@ export function sleep(ms: number = 0): Promise<any> {
   return new Promise<any>((resolve, reject) => {
     setTimeout(resolve, ms);
   });
-}
+}