Some of the BCD tests were failing because of recent changes on how we write float numbers as strings. The results have not changed; just the way they are presented (the precision of the floating numbers) have changed. Therefore, I just replaced the previous baselines by the modified versions.
STYLE: Renamed posteriors list to partials
New option added to that defaults to off for FORCE_EXTERNAL_BUILDS. This needs to be turned ON to allow updating of external packages. Needed to split the ExternalProject command and argument into separate varables for their effect to work. Otherwise they were having no noticiable effect on the build system.
The logic for re-running data sinks was not correct.