Edits .editorconfig.

Now supposedly enforces crlf (Windows) newlines in dm/dmm files when using the webUI, similar to .gitattributes.
Also adds standard .yml and .py settings commonly found in other .editorconfigs I've looked at, because why not?

.editorconfig

@@ -1,4 +1,22 @@
+root = true
+
 [*]
 insert_final_newline = false
+trim_trailing_whitespace = true
+
+[*.dm]
+end_of_line = crlf
 indent_style = tab
 indent_size = 4
+
+[*.dmm]
+end_of_line = crlf
+
+[*.py]
+indent_style = space
+indent_size = 4
+
+[*.yml]
+indent_style = space
+indent_size = 2
+