Changed convergence function to fall back to project
Changed convergence function to fall back to project

level convergence if a project is excluded by all scrapers at
the manifest level. This is to optimize for medium duration fallout of
a project from all scrapers, where valid project stats for that project
are still in manifests within the retention window.

gridcoin/Gridcoin-Research,theMarix/Gridcoin-Research,Git-Jiro/Gridcoin-Research,caraka/gridcoinresearch,gridcoin/Gridcoin-Research,caraka/gridcoinresearch,theMarix/Gridcoin-Research,Git-Jiro/Gridcoin-Research,theMarix/Gridcoin-Research,gridcoin/Gridcoin-Research,gridcoin/Gridcoin-Research,caraka/gridcoinresearch,theMarix/Gridcoin-Research,Git-Jiro/Gridcoin-Research,caraka/gridcoinresearch,gridcoin/Gridcoin-Research,theMarix/Gridcoin-Research,gridcoin/Gridcoin-Research,caraka/gridcoinresearch,theMarix/Gridcoin-Research,Git-Jiro/Gridcoin-Research,Git-Jiro/Gridcoin-Research,caraka/gridcoinresearch