Improve automatic scaling for 3d plots

[NickDraper]

This issue was originally TRAC 6989

3D plots currently always include the whole workspace.

Alter them to only take selected data row if only a few are selected.

Also the default scaling of the graph is poor. if you select something with 10 spectra, 1000 time bins and counts up to 10000, the resulting graph is almost flat and useless.

[NickDraper]

@NickDraper (2013-07-26T13:55:01):
Moved to backlog at the code freeze for R2.6

---

@NickDraper (2014-02-14T11:04:59):
Bulk move to assigned at the introduction of the triage step

[NickDraper]

archived