edit start/end of alignment sequence relocates annotation derived from structure

This could be construed as a feature (but maybe not..):

1. import a PDB structure into Jalview with secondary structure annotation enabled.
2. open the edit name/description dialog and change the sequence numbering by entering e.g. "newid/20-50"
3. copy and paste sequence to new window - note annotation is now shifted

The relocation is due to the edit operation only affecting the local alignment sequence's start/end. It doesn't happen immediately for annotation rows because local positional annotation doesn't get updated, but sequence features will be affected immediately.
Since the parent sequence's start/end is unaffected, PDB highlighting is unaffected, but because the secondary structure annotation is in the wrong place, the utility of colour-by-annotation is lost.