Custom build environment in JS2

[muratmaga]

I think it makes sense to have a custom build environment with all the build/runtime dependencies of SlicerMorph (e.g., Surface Markups) included so that we can have a custom build ready to be included in the MorphoCloud when we need to integrate a change to SlicerMorph (or need a new feature of Slicer to be available to the people).

@pieper commented that using 64 core instance, full build takes about 30 minutes. I think this will be useful to investigate during the PW.

Downside is that full extension catalogue will not be available to the user

Currently we want these extensions to be available to the user:

SlicerMorph
SegmentEditorExtraEffects
Sandbox
Model2Model distance
WrapSurfaceSolidify
SurfaceMarkups
IGT
SlicerANTs (when done)
DeCA (when pushed to the extension catalogue)
MorphoDepot