use CRLF line endings in README.txt file for compatibility with more Windows text editors

.editorconfig

@@ -18,6 +18,9 @@ indent_size = 2
 [*.csproj]
 insert_final_newline = false
 
+[README.txt]
+end_of_line=crlf
+
 ##########
 ## C# formatting
 ## documentation: https://docs.microsoft.com/en-us/visualstudio/ide/editorconfig-code-style-settings-reference

.gitattributes

@@ -1,2 +1,3 @@
 # normalise line endings
 * text=auto
+README.txt text=crlf