fs: deglobalise the config #4685

This is done by making fs.Config private and attaching it to the
context instead.

The Config should be obtained with fs.GetConfig and fs.AddConfig
should be used to get a new mutable config that can be changed.

backend/fichier/fichier_test.go

@@ -4,13 +4,11 @@ package fichier
 import (
 	"testing"
 
-	"github.com/rclone/rclone/fs"
 	"github.com/rclone/rclone/fstest/fstests"
 )
 
 // TestIntegration runs integration tests against the remote
 func TestIntegration(t *testing.T) {
-	fs.Config.LogLevel = fs.LogLevelDebug
 	fstests.Run(t, &fstests.Opt{
 		RemoteName: "TestFichier:",
 	})