#3 Multithreaded compressors

[Lazy_Kent]

Please add an ability to use multi-threaded compression file utilities (if installed, optionally), such as pigz(1), pixz(1), pbzip2(1).

For example: 'to-xz' runs xz(1) and 'to-xz -p' runs pixz(1).

[Brian Lindholm]

Multi-threaded compression has been added to the to-gzip, to-bzip, to-lzip, to-lzma, and to-xz utilities as of littleutils-1.0.34.