FolderStorage

Abstraction around POSIX folders. This allows us to switch between different types of storage (e.g. POSIX vs. Cloud storage) in packages that use the abstract Container type found in https://github.com/ChevronETC/AbstractStorage.jl. In addition, FolderStorage threads read operations using PARTR.

FolderStorage can be convenient for package development but is not intended for direct use.