Segment renaming is lost when changing order

[alguerre]

When the segments ordering is modified they recover their original name.

Steps to reproduce

1. Load island_1.gpx
2. Load island_2.gpx
3. Rename island_1.gpx -> i1
4. Rename island_2.gpx -> i2
5. Change order: i2, i1
6. Original names are back

Before re-order

After re-order