dataset bundler updates

Bump bzip2 from 0.4.3 to 0.4.4

Bumps [bzip2](https://github.com/alexcrichton/bzip2-rs) from 0.4.3 to 0.4.4.
- [Release notes](https://github.com/alexcrichton/bzip2-rs/releases)
- [Commits](https://github.com/alexcrichton/bzip2-rs/commits/0.4.4)

---
updated-dependencies:
- dependency-name: bzip2
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

bump version for arxmliv 2020 docs

two separate warning sets for 2019 dataset

patch release with first feedback on History feature and minor fixes

refine table display; drop invalid from vega diagram (irrelevant)

update readme

experiment: bash script for bundling 08.2018 arxmliv

release 0.3.0

Merge pull request #24 from dginev/switch-to-diesel

Switch to diesel.rs