BUG: Fix units when reloading scenes

Restoring the selection node unit references shall not just be done when
closing scene, but also when loading or restoring a scene.
To simplify, it should be done anytime the selection node is modified.
When Clear() is called, singletons are reset, which means they loose their
node references. Which should trigger a ModifiedEvent (see next commit)
that is caught by the unit logic that can restore the unit references.

Fixes #3152

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22222 3bd1e089-480b-0410-8dfb-8563597acbee
BUG: vtkMRMLNode::Reset() should trigger ModifiedEvent if needed

 * Remove the dangerous method
vtkMRMLNode::CopyWithSceneWithoutModifiedEvent():
 ** Modifying a node should never be silent, at least one ModifiedEvent
should be triggered.
 * Copying references should not be silent: ModifiedEvent and
NodeReference*Events should be triggered.

The fix ensures resetting() the selection node triggers at least 1
ModifiedEvent.

Fixes #3152

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22223 3bd1e089-480b-0410-8dfb-8563597acbee
COMP: Disable OpenSSL parallel build

Commit r22220 enabled SSL support and also included a patch allowing
OpenSSL to be built in parallel. Parallel build prevent the library
from being built on MacOSX factory. Waiting this is fixed and in order
to restore the nightly build, the build is forced to be sequential.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22224 3bd1e089-480b-0410-8dfb-8563597acbee