Add a way to see why a workspace is not valid for an algorithm

[mantid-builder]

This issue was originally TRAC 5607

Original Reporter: Russell Taylor

The fact that the algorithm dialog's input workspace combo-box only shows valid workspaces is very useful for reducing clutter, but does mean that you can't see why a particular workspace is not valid (unless you go off and try to run it via python).
This can be awkward if it's not obvious to the user why it isn't valid. Add some (not too intrusive) mechanism so that a user can find out why invalid workspaces were excluded.

[mantid-builder]

@NickDraper (2012-08-10T12:45:17):
http://www.mantidproject.org/Release_Notes_2_2_Full_List

---

@NickDraper (2012-10-28T11:42:56):
Moved to release 2.4

---

@NickDraper (2013-01-28T09:23:35):
Moved at the code freeze for release 2.4

---

@NickDraper (2013-04-29T09:50:08):
Moved to r2.6 at the end of r2.5

---

@NickDraper (2013-07-26T13:59:11):
Moved to the Backlog after the code freeze for R2.6

---

@NickDraper (2014-02-14T11:07:57):
bulk move to assigned at the into of the triage step

[NickDraper]

Not asked for for a long time - archived