Update readme

Author: msmakouz

README.md

@@ -22,6 +22,70 @@ You can install the package via composer:
 composer require roadrunner-php/version-checker
 ```
 
+## Usage
+
+Use the `RoadRunner\VersionChecker\VersionChecker` methods to check the compatibility of the installed RoadRunner
+version. The VersionChecker class has three public methods:
+
+- **greaterThan** - Checks if the installed version of RoadRunner is **greater than or equal** to the specified version.
+  If no version is specified, the minimum required version will be determined based on the minimum required version of
+  the `spiral/roadrunner` package.
+- **lessThan** - Checks if the installed version of RoadRunner is **less than or equal** to the specified version.
+- **equal** - Checks if the installed version of RoadRunner is **equal** to the specified version.
+
+All three methods throw an `RoadRunner\VersionChecker\Exception\UnsupportedVersionException` if the installed version
+of RoadRunner does not meet the specified requirements. If RoadRunner is not installed, a
+`RoadRunner\VersionChecker\Exception\RoadrunnerNotInstalledException` is thrown.
+
+```php
+use RoadRunner\VersionChecker\VersionChecker;
+use RoadRunner\VersionChecker\Exception\UnsupportedVersionException;
+
+$checker = new VersionChecker();
+
+try {
+    $checker->greaterThan('2023.1');
+} catch (UnsupportedVersionException $exception) {
+    var_dump($exception->getMessage()); // Installed RoadRunner version `2.12.3` not supported. Requires version `2023.1` or higher.
+    var_dump($exception->getInstalledVersion()); // 2.12.3
+    var_dump($exception->getRequestedVersion()); // 2023.1
+}
+
+try {
+    $checker->lessThan('2.11');
+} catch (UnsupportedVersionException $exception) {
+    var_dump($exception->getMessage()); // Installed RoadRunner version `2.12.3` not supported. Requires version `2.11` or lower.
+    var_dump($exception->getInstalledVersion()); // 2.12.3
+    var_dump($exception->getRequestedVersion()); // 2.11
+}
+
+try {
+    $checker->equal('2.11');
+} catch (UnsupportedVersionException $exception) {
+    var_dump($exception->getMessage()); // Installed RoadRunner version `2.12.3` not supported. Requires version `2.11`.
+    var_dump($exception->getInstalledVersion()); // 2.12.3
+    var_dump($exception->getRequestedVersion()); // 2.11
+}
+```
+
+### Path to the RoadRunner binary
+
+To configure the `VersionChecker` to search for the RoadRunner binary in a location other than the default
+(application root with a rr filename), you can bind the `RoadRunner\VersionChecker\Version\InstalledInterface`
+within application container using the `RoadRunner\VersionChecker\Version\Installed` class and passing the desired
+file path as the **$executablePath** parameter. After that, you can retrieve the VersionChecker class from
+application container.
+
+Example with Spiral Framework container:
+
+```php
+use RoadRunner\VersionChecker\Version\InstalledInterface;
+use RoadRunner\VersionChecker\Version\Installed;
+
+$container->bindSingleton(InstalledInterface::class, new Installed(executablePath: 'some/path'));
+$checker = $container->get(VersionChecker::class);
+```
+
 ## Testing
 
 ```bash