Add ability to flush cache via function directly. Update readme

Author: Aaron Holbrook

README.md

@@ -56,3 +56,8 @@ Make a GET request to your site's URL with the query parameter `?wpe-cache-flush
 ```
 GET http://example.com/?wpe-cache-flush=$private_key
 ```
+
+You can also call the flush function directly from your code via 
+```php
+\A7\WPE_Cache_Flush\cache_flush()
+```

composer.json

@@ -3,7 +3,7 @@
 	"description": "Programmatically flush the WP Engine Cache",
 	"type": "library",
 	"license": "UNLICENSE",
-	"version": "0.2.3",
+	"version": "0.3.0",
 	"authors": [
 		{
 			"name": "A7",

wpe-cache-flush.php

@@ -42,9 +42,26 @@ function get_flush_token() {
 		return;
 	}
 
+	$error = cache_flush();
+
+	header( "Content-Type: text/plain" );
+	header( "X-WPE-Host: " . gethostname() . " " . $_SERVER['SERVER_ADDR'] );
+
+	echo "All Caches were purged!";
+	echo $error;
+
+	exit( 0 );
+} );
+
+/**
+ * Allow cache flushing to be called independently of web hook
+ *
+ * @return string|bool
+ */
+function cache_flush() {
 	// Don't cause a fatal if there is no WpeCommon class
 	if ( ! class_exists( 'WpeCommon' ) ) {
-		return;
+		return false;
 	}
 
 	if ( function_exists( 'WpeCommon::purge_memcached' ) ) {
@@ -72,11 +89,5 @@ function get_flush_token() {
 		}
 	}
 
-	header( "Content-Type: text/plain" );
-	header( "X-WPE-Host: " . gethostname() . " " . $_SERVER['SERVER_ADDR'] );
-
-	echo "All Caches were purged!";
-	echo $error;
-
-	exit( 0 );
-} );
+	return $error;
+}