Conflict between IPython console in MSlice and MantidWorkbench

[mducle]

Describe the bug
In some (hard to reproduce) cases, there is a conflict between the IPython console in the Mantid Workbench and that of MSlice; A user has reported that after running Workbench+MSlice for some time, the IPython console in Workbench becomes unresponsive and only the console in MSlice works. I've been unable to reproduce this so far.

Expected behavior
If this recurs, it might be a good idea to disable the IPython console on MSlice instances that are run from within the Workbench (I think this was the behaviour a few versions ago).