Merge pull request mgechev#95 from xied5531/master

fix binarysearch.js, return -1 if not found

Author: mgechev

src/searching/binarysearch.js

@@ -38,7 +38,7 @@
       }
       middle = Math.floor((left + right) / 2);
     }
-    return -middle - 1;
+    return -1;
   }
 
   exports.binarySearch = binarySearch;