fixed README typo

README.md

@@ -124,7 +124,7 @@ For available options see [options](#options).
 Usage:
 ```sh
 javascript-obfuscator in.js [options]
-javascript-obfuscator in.js -output out.js [options]
+javascript-obfuscator in.js --output out.js [options]
 ```
 
 If the destination path is not specified through `--output` option, obfuscated code will saved into input file directory with name like `INPUT_FILE_NAME-obfuscated.js`

src/storages/ArrayStorage.ts

@@ -45,6 +45,7 @@ export abstract class ArrayStorage <T> implements IStorage <T> {
      */
     public getKeyOf (value: T): number | null {
         const key: number = this.storage.indexOf(value);
+
         return key >= 0 ? key : null;
     }