Export serialized bags

[mikejritter]

Resolves: https://jira.lyrasis.org/browse/FCREPO-3206

• Add command line argument for specifying serialization and format for export
  • --bag-serialization | -s
• Serialize bags when specified during export
• Update README to include documentation for bag serialization

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Testing

1. Start a fresh fedora repository, e.g. with fcrepo4-docker FEDORA_TAG=5.1.0 docker-compose up -d
2. Create a binary in the repository
3. Create a bag-config.yml for export

   bag-info.txt:
   Source-Organization: fcrepo-import-export
   Organization-Address: localhost
   External-Description: Serialized BagIt Bag

4. Run the exporter
   • Can be done for each of tar, tgz, and zip

     java -jar target/fcrepo-import-export-0.4.0-SNAPSHOT.jar -s tar --mode export --resource http://localhost:8080/fcrepo/rest --dir fcrepo-3206  --binaries --bag-profile beyondtherepository --bag-config bag-config.yml --user fedoraAdmin:secret3

5. Check that the exported bag is valid using either tar or unzip
   • tar tvf fcrepo-3206.tar
   • tar tzvf fcrepo-3206.tar.gz
   • unzip -l fcrepo-3206 .zip