Update package descriptions and keywords (package.json)

[warm-coolguy]

https://github.com/Dataport/polar/pull/108#discussion_r1500310642

As described in this thread, keywords and descriptions are currently not ideal. This is a minor thing, since coding users will be directed to the README.md or API.md files, which are fine. However, to fully support npm search, it's plausible to tackle this eventually.

Currently, most descriptions are just the package name or a copy from the README.md, and most keywords fields are currently not used.