Finish migration to setuptools_scm

Constrain setuptools_scm version

- Add module entry points for xq and tomlq

- yq -y: Induce quoting of string scalars that start with 08 and 09

Revert "Do not interpret characters that cannot be parsed in octal as…

… int (#176)"

- tomlq: Use tomllib on Python 3.11 when not round-tripping

- xq: Support in-place XML editing

- Do not interpret characters that cannot be parsed in octal as int (#176)

- test.py: use valid values for jsonargs. Fixes #172

- Allow editing toml in place (#171)

- Documentation improvements

- Allow XML documents to be streamed with --xml-item-depth

- Relax tomlkit dependency version range to preserve Python 3.6 compa…

…tibility (#165)

- Use tomlkit instead of toml

- Add security policy

- Documentation and release infrastructure improvements