Update README.md [skip ci]

Author: z4kn4fein

README.md

@@ -31,7 +31,7 @@ echo $version->getPreRelease();     // alpha.12
 echo $version->getBuildMeta();      // build.34
 echo $version->getVersionString();  // 2.5.6-alpha.12+build.34
 ```
-#### Compare two versions
+#### Comparing two versions
 ```php
 <?php
 
@@ -54,4 +54,4 @@ echo $version->isLessThanOrEqual('2.5.6-alpha.12');  // true
 echo $version->isEqual('2.5.6-alpha.12+build.56');   // true
 ```
 ## Invalid version handling
-When the version parsing fails due to an invalid format, the library throws a specific `VersionFormatException`.
+When the version parsing fails due to an invalid format, the library throws a specific `VersionFormatException`.