Expose the context to the initialize and finalize functions for Output
Processors. This was found to be necessary for the upcoming PostgreSQL
Output Processor.
In commit d2ece we are now tracking augmentations which are used during a
run in the run_config via the context when installing augmentations.
Update the Process command and its ProcessContext with a dummy method
to relect this change.
Running additional processors will generate new metrics and artifacts.
Update the serialized metadata with the new artifacts/metrics after
running all processors.
Add process command to run output processors over data produced by
a previous run.
Default processing is to skip the processors that were used during
the run and to process the specified directory only. Options to
use additional processors, force reprocessing and allow a directory
walk to discover additional output directories.
