Added editor config file.

.editorconfig

@@ -0,0 +1,10 @@
+# editorconfig.org
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true

public/index.php

@@ -9,7 +9,7 @@
 });
 
 $app->get('/', function ($request, $response, $args) {
-	$response = $response->withHeader('Content-Type', 'application/json; charset=UTF-8');
+    $response = $response->withHeader('Content-Type', 'application/json; charset=UTF-8');
     return $response->withStatus(200)->write('{"message":"It\'s working"}');
 });