Support specifying multiple host flags for various commands

The `dump`, `find`, `forget`, `ls`, `mount`, `restore`, `snapshots`,
`stats` and `tag` commands will now take into account multiple
`--host` and `-H` flags.

internal/fuse/root.go

@@ -19,7 +19,7 @@ import (
 // Config holds settings for the fuse mount.
 type Config struct {
 	OwnerIsRoot      bool
-	Host             string
+	Hosts            []string
 	Tags             []restic.TagList
 	Paths            []string
 	SnapshotTemplate string

internal/fuse/snapshots_dir.go

@@ -234,7 +234,7 @@ func updateSnapshots(ctx context.Context, root *Root) error {
 		return nil
 	}
 
-	snapshots, err := restic.FindFilteredSnapshots(ctx, root.repo, root.cfg.Host, root.cfg.Tags, root.cfg.Paths)
+	snapshots, err := restic.FindFilteredSnapshots(ctx, root.repo, root.cfg.Hosts, root.cfg.Tags, root.cfg.Paths)
 	if err != nil {
 		return err
 	}