This important method updates the Account/Groups context of a DisplayableLinkImpl,
either from the AG context of the last node having one, or from one of
the following nodes in the same ACS, or, if there is no current AG context,
through all the connected nodes from the same ACS.
This important method updates the Account/Groups context of a DisplayableLinkImpl,
either from the AG context of the last node having one, or from one of
the following nodes in the same ACS, or, if there is no current AG context,
through all the connected nodes from the same ACS.
This is the only method to call just after getInstance() to
set the right beamer pane, that is always a JPanel so far,
and to initialize it with all the panels associated to the
properties of the base object to display.