add .editorconfig

.editorconfig

+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+
+[*.{java,kt,sh,md}]
+indent_style = space
+indent_size = 4
+
+[*.xml]
+indent_style = tab
+indent_size = 4
+
+[*.yml]
+indent_style = space
+indent_size = 2