Allow deleting data to save space

[d-krupke]

The data saved by AlgBench is supposed to enable you to debug stuff and investigate observations. However, it can accumulate to many gigabytes.

1. You may want to clean up the results but still mark the parameters as already run and processed.
2. You may want to delete old stdout captures etc., without deleting the whole entry in order to have a more efficient database.

Write an efficient function that can reduce that data without deleting the "already run" property. There needs to be some thoughts about how to deal with the individual elements.

[d-krupke]

Can be done easily with apply.