Ignore /secure-file folder

Created by nuget install secure-file -excludeversion
Used by build server to decrypt secure files.

Author: angularsen

.gitignore

@@ -251,4 +251,7 @@ paket-files/
 
 # Custom for this repo
 Artifacts
-**/Thumbs.db
+**/Thumbs.db
+
+# Build server tooling
+/secure-file