package command: -z now takes an argument to specify the compression method.

The upcoming change to use zstd by default will make the -z no-argument
variant obsolete, so instead we need to support passing "zstd" or "zlib"
to actually indicate the compression method we want to use.

package command: Remove duplicate code in recompress.

Package Kit: add Zstd compression.

Change-Id: Idbdb7cf1bde659046a88ea69a76e3b5fc4cd7013
Reviewed-on: https://review.haiku-os.org/323
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

package recompress: Small cleanup

BPackageWriter::Recompress(): Change param to BPositionIO*

Besides that this is a nicer interface, it allows us to get a the HPKG
header as a side effect of initializing the reader, thus preventing
seeking backward in the file. This makes "package recompress - <file>"
work.

package recompress: Add stdin/stdout support

stdin doesn't work quite yet. We'll need to convince the BPackageReader
to skip parsing the TOC and package attributes sections.

package: Explicitly use B_HPKG_COMPRESSION_NONE

package: Add command recompress

The streaming feature for -0 is missing yet.

package recompress: Small cleanup

BPackageWriter::Recompress(): Change param to BPositionIO*

Besides that this is a nicer interface, it allows us to get a the HPKG
header as a side effect of initializing the reader, thus preventing
seeking backward in the file. This makes "package recompress - <file>"
work.

package recompress: Add stdin/stdout support

stdin doesn't work quite yet. We'll need to convince the BPackageReader
to skip parsing the TOC and package attributes sections.

package: Explicitly use B_HPKG_COMPRESSION_NONE

package: Add command recompress

The streaming feature for -0 is missing yet.