Redesigning wrapper to correctly run from pipeline files.

[jlvdb]

In the current implementation, the YAW wrapper cannot be run as a ceci pipeline because the order in which stages are run is not deterministic.

Problems

1. Ceci may decide to run the YawCacheDrop stage before the correlation measurements have even started.
2. When a new data set is cached and is supposed to inherit the patch centers from a different data set, the caching of these data sets is not guaranteed to happen in the correct order.

Solutions

1. Remove the YawCacheDrop stage entirely and leave it to the user to clean up the temporarily cached data, as they may be reused if neither the catalog nor the patch centers change.
2. Add an additional (optional) link for YawCacheCreate instances to share patch centers and ensure execution in the correct order.