builds the delta to the original scriptMapping. Returns a List of ScriptListEntry objects,
where the id is set to ScriptListWrapper.ID_SCRIPT_REMOVED for scripts that where removed from
the script list and where the id is set to ScriptListWrapper.ID_SCRIPT_ADDED for scripts that
where added to the script list. ID_SCRIPT_UPDATED for scripts that have been updated.
id - the id of the type or assignment for the script mapping
a list of ScriptEntry objects which have changed in the script list relative to
the original scriptMapping.