scripts/contrib/image-manifest: add new script

image-manifest: script to generate product/image specific BOM

The image-manifest script generates image specific reports based on
an image manifest file. Currently there is data generated by buildhistory,
pkgdata, and license manifest but this data is poorly formated and spread
across multiple text files. This script can generate a single JSON output
file that is machine readable by other tools.

The manifest-info collects package information and stores the information
in a tarball. manifest-info can be configured using a json configuration
file. The default configuration including all possible options can be
dumped using the dump-config subcommand.

image-manifest takes an image manifest file as input to get the runtime
dependencies. As an option image-manifest can also use the build dependency
file, pn-buildlist, to get the build dependencies excluding native
packages.

This script extends the oe-image-manifest script [0] done by Paul Eggleton

[0]
https://github.com/intel/clear-linux-dissector-web/blob/master/layerindex/static/files/oe-image-manifest



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usage: image-manifest [-h] [-d] [-q] <subcommand> ...

Image manifest utility

options:
  -h, --help     show this help message and exit
  -d, --debug    Enable debug output
  -q, --quiet    Print only errors

subcommands:
  recipe-info    Get recipe info
  list-depends   List dependencies
  list-recipes   List recipes producing packages within an image
  list-packages  List packages within an image
  list-layers    List included layers
  dump-config    Dump default config
  manifest-info  Export recipe info for a manifest
Use image-manifest <subcommand> --help to get help on a specific command

Co-developed-by: Paul Eggleton <bluelightning@bluelightning.org>
Signed-off-by: Anders Wallin <anders.wallin@windriver.com>
Signed-off-by: Saul Wold <saul.wold@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>