feature(editorconfig) add

.editorconfig

@@ -0,0 +1,14 @@
+# This file is for unifying the coding style for different editors and IDEs
+# http://editorconfig.org
+
+# top-most EditorConfig file
+root = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 4