Fixes in ratarmount

• Add --recursion-depth argument for more fine-grained recursion control.
• Add support to show a joined view of split files, e.g., .001, and also support split archives.
• Add --use-backend option to choose between multiple available backends, e.g., 'lzmaffi' and 'xz' for xz files.
• Add support for pragzip when it has been installed and specified with '--use-backend pragzip'.
  Pragzip offers unique parallelized decompression of arbitrary gzip files. Using a 12-core processor,
  it can show speedups of 12 over gzip and speedups of 8 over pigz for sequentially decoding base64 files.
  Furthermore, similar to indexed_bzip2 it is based on a block cache and therefore can substantially speed up
  concurrent access streams as might happen when accessing multiple files through ratarmount concurrently.
  Currently, indexed_gzip will still be used to create the index in the first pass and pragzip is used
  for subsequent accesses with '--use-backend pragzip'.

Fixes in ratarmountcore

• AutoMountLayer now takes a 'recursionDepth' argument instead of 'recursive'.
• Fix handling of paths in zip and rar files that contain '../'.
• Add backend prioritization option to SQLiteIndexedTar.
• Add support for pragzip.