Add .editorconfig file.

vext01 · vext01 · commit 97f1eb41a04c · 2021-10-29T15:15:59.000+01:00
Laurie and I like the idea.
diff --git a/.editorconfig b/.editorconfig
@@ -0,0 +1,5 @@
+root = true
+
+[*.{cpp,cc,c,h}]
+indent_style = space
+indent_size = 2
