Prepare for Contao 5.7 (#428)

Co-authored-by: Andreas Schempp <andreas.schempp@terminal42.ch>

Author: qzminski

.editorconfig

@@ -0,0 +1,20 @@
+# EditorConfig is awesome: http://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+[*.{php,html5,twig,yml,json}]
+indent_style = space
+indent_size = 4
+
+[*.{svg,min.css,min.js}]
+insert_final_newline = false
+
+[*.md]
+trim_trailing_whitespace = false