update readme add --save

Author: miladd3

README.md

@@ -8,7 +8,7 @@
 
 ## Install
 
-`npm install vue-simple-password-meter`
+`npm install vue-simple-password-meter --save`
 
 ## Usage
 
@@ -101,7 +101,7 @@ export default {
   methods: {
     onScore({ score, strength }) {
       console.log(score); // from 0 to 4
-      console.log(strength); // one of : 'risky', 'guessable', 'weak', 'safe' or 'secure' 
+      console.log(strength); // one of : 'risky', 'guessable', 'weak', 'safe' , 'secure' 
       this.score = score;
     }
   }