[DEV-11651] Reduce base install size by making Msgpack, Numpy, and Pandas optional dependencies

[mawelborn]

Summary

Make large dependencies like Numpy and Pandas optional to reduce the base install size of the client. These are required by only a handful of uncommon calls, yet represent 75% of the install size. This will better support customers who use the client in AWS Lambdas where they're limited to 250Mb.

[michael@macbook indico-client-python]$ du -hd 1 . | grep venv
 37M    ./venv-base
146M    ./venv-all

Changelog

• Removed pillow as it appears to be unneeded.
• Made msgpack and numpy optional as they are only used for specific deserialization functions.
  • Available via the indico-client[deserialization] or indico-client[all] extras.
• Made pandas optional as it is only used for creating image datasets and retrieving exports.
  • Available via the indico-client[datasets], indico-client[exports], or indico-client[all] extras.
  • Pandas could be dropped entirely if CreateDataset manipulated CSVs with the native csv module and DownloadExport returned a CSV string instead of a dataframe.
• Added instructional errors when functionality is used that requires optional dependencies that are not installed.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• Jira story/task is put into PR title
• Code has been self-reviewed
• Hard-to-understand areas have been commented
• Documentation has been updated
• My changes generate no new warnings
• Unit tests have been added for base functionality and known edge cases
• Any dependent changes have been merged and published in downstream modules