update readme

README.md

@@ -7,7 +7,7 @@ An Amazon S3 component for Yii2.
 [![Total Downloads](https://poser.pugx.org/frostealth/yii2-aws-s3/downloads)](https://packagist.org/packages/frostealth/yii2-aws-s3)
 [![Latest Unstable Version](https://poser.pugx.org/frostealth/yii2-aws-s3/v/unstable)](https://packagist.org/packages/frostealth/yii2-aws-s3)
 
-> Yii2 AWS S3 uses [semantic versioning](http://semver.org/).
+> Yii2 AWS S3 uses [SemVer](http://semver.org/).
 
 > Version 2.x requires PHP 7. For PHP less 7.0 use [1.x](https://github.com/frostealth/yii2-aws-s3/tree/1.x).
 
@@ -57,8 +57,8 @@ $result = $s3->commands()->upload('filename.ext', '/path/to/local/file.ext')->se
 
 $result = $s3->commands()->restore('filename.ext', $days = 7)->execute();
 
-/** @var bool $isExisting */
-$isExisting = $s3->commands()->exist('filename.ext')->execute();
+/** @var bool $exist */
+$exist = $s3->commands()->exist('filename.ext')->execute();
 
 /** @var string $url */
 $url = $s3->commands()->getUrl('filename.ext')->execute();
@@ -84,8 +84,8 @@ $result = $s3->upload('filename.ext', '/path/to/local/file.ext');
 
 $result = $s3->restore('filename.ext', $days = 7);
 
-/** @var bool $existence */
-$existence = $s3->exist('filename.ext');
+/** @var bool $exist */
+$exist = $s3->exist('filename.ext');
 
 /** @var string $url */
 $url = $s3->getUrl('filename.ext');