Add a limit configuration to CollectionReader for number of output CAS

[Erfans]

Sometimes it is difficult/infeasible to limit number of output CAS by only using include/exclude patterns. Such as a folder with many similarly named files, or zip files, or when each file extracts to multiple CAS. I'm suggesting a limit configuration be added perhaps to ResourceCollectionReaderBase.

[reckart]

Sounds like a useful idea and should be easy to implement.

[Erfans]

Then I can provide a PR.

[reckart]

@Erfans sure, happy for it! Please make sure to check out our contribution guidelines when you do so.