Make the version check more informative

Previously, the PHP version check run at the start of the script would display `PHP Parallel Lint requires PHP 5.3.0 or newer.` if the PHP version was too low.

The message has been updated to include the currently detected PHP version and the path to the PHP binary.

Note: both constants used are available in PHP cross-version.

parallel-lint

@@ -31,7 +31,15 @@ either expressed or implied, of the FreeBSD Project.
  */
 
 if (!defined('PHP_VERSION_ID') || PHP_VERSION_ID < 50300) {
-    fwrite(STDERR, "PHP Parallel Lint requires PHP 5.3.0 or newer." . PHP_EOL);
+    fwrite(
+        STDERR,
+        sprintf(
+            'PHP Parallel Lint requires PHP 5.3.0 or newer.' . PHP_EOL
+            . 'You are using PHP %s (%s).' . PHP_EOL,
+            PHP_VERSION,
+            PHP_BINDIR
+        )
+    );
     exit(254);
 }