Editing not working correctly during a second session

[horsburgh]

After the following occurs, editing stops working correctly:

1. I open an edit session on a series and make some changes
2. I save my edits
3. I stop editing
4. I start editing again
5. I make some edits (they are not drawn correctly). If I do an interpolation, the interpolated points and the original points are still drawn on the plot.
6. I save my edits (they are not saved)
7. I stop editing (the series is the same as it was before).
   We suspect that this has something to do with the series not being correctly selected and/or the check box not being handled correctly after the first editing session.

[AmberSJones]

This sounds similar to issues that @PhilSuiter has reported- after editing and saving and then trying to work on the series again, nothing quite works correctly.

[AmberSJones]

Ready for testing in the 1.2.3 release.

[AmberSJones]

This is addressed. I can follow @horsburgh 's steps and the behavior is as expected.