[bugfix] panel_ieeg

[chinmaychinara91]

Issue-1: If implantation is started and there is a 3DMRI+isosurface figure open, unexpected things happens. Solution: https://github.com/brainstorm-tools/brainstorm3/pull/701/commits/fad6568ee413e061af912e16c8270a3d836fdab6

Issue-2: Double-clicking on the SEEG/ECOG ("number of channels") channel file in the functional tab only opens the cortex figure for ECOG and ECOG+SEEG. Solution: https://github.com/brainstorm-tools/brainstorm3/pull/701/commits/9452f2f21fc3685b2ff60ae9705360b7246bc8cc

Discussion: https://neuroimage.usc.edu/forums/t/display-sensors-cortex-opens-mri-viewer-in-addition-to-cortex-view/46083/2 Do we need to have MRI Viewer display for all surface types by default ? If no then this is the proposed solution: https://github.com/brainstorm-tools/brainstorm3/pull/701/commits/3ccd367251ad92d75fde12d652c21427ebd45c0e

[rcassani]

Discussion: https://neuroimage.usc.edu/forums/t/display-sensors-cortex-opens-mri-viewer-in-addition-to-cortex-view/46083/2 Do we need to have MRI Viewer display for all surface types by default ? If no then this is the proposed solution: https://github.com/brainstorm-tools/brainstorm3/commit/3ccd367251ad92d75fde12d652c21427ebd45c0e

This was introduced in #699 with the commit 60cc127 to patch another bug.

https://github.com/brainstorm-tools/brainstorm3/pull/699/commits/60cc1273f879314276f61f2edae683b4689eeb22

[rcassani]

This PR has been closed without merging.

The idea is to refactor the IEEG updated features in one PR, to properly address these issues, and others. See #710