Repalce tab with 4 spaces per PEP-8

Thanks, Reddit!

Author: chenster

.editorconfig

@@ -0,0 +1,12 @@
+root = true
+
+[*]
+indent_style = space
+indent_size = 4
+charset = utf-8
+trim_trailing_whitespace = false
+insert_final_newline = false
+
+[*.py]
+indent_style = space
+indent_size = 4