Adding upstream version 0.31.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

.editorconfig

@@ -0,0 +1,24 @@
+# see http://editorconfig.org/
+
+root = true
+
+[*]
+trim_trailing_whitespace = true
+insert_final_newline = true
+end_of_line = lf
+charset = utf-8
+tab_width = 4
+indent_style = space
+
+[{Makefile,go.mod,go.sum,*.go,.gitmodules}]
+indent_style = tab
+indent_size = 8
+
+[*.{yaml,yml}]
+indent_size = 2
+indent_style = space
+
+[*.md]
+indent_style = space
+max_line_length = 80
+indent_size = 4