Add .editorconfig (#149193)

This adds an .editorconfig file to automatically configure devs local Editors / IDEs with the basic formatting rules of the project.

List of supported editors: https://editorconfig.org/#pre-installed

Pull Request resolved: https://github.com/pytorch/pytorch/pull/149193
Approved by: https://github.com/malfet

.editorconfig

@@ -0,0 +1,14 @@
+root = true
+
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+# Python
+[*.py]
+indent_style = space
+indent_size = 4
+
+# Make
+[Makefile]
+indent_style = tab