return this from kepi.safe() and kepi.applyTo()

README.md

@@ -49,6 +49,9 @@ But sometimes you need to add stuff dynamically
 
     app.use(kepi.middleware());
 
+### If you just want to mimic (more or less) [helmet](https://www.npmjs.com/package/helmet)
+
+    app.use(kepi().safe().middleware());
 
 ## API
 

kepi.js

@@ -24,7 +24,8 @@ class Kepi {
     let headerNames = Object.keys(this.headers);
     headerNames.forEach( (headerName) => {
       this.headers[headerName].applyTo(response);
-    });
+    });   
+    return this;
   }
 
 
@@ -52,7 +53,8 @@ class Kepi {
     let allSafe = Object.assign({}, this.options.SAFE, this.options.safe);
     Object.keys(allSafe).forEach( (headerName) => {
       this.header(headerName).safe();
-    });
+    });    
+    return this;
   }
 
   _fullName(name) {