interface changes
- introduce `SubCorpus` (instead of `Dump`) (closes 64)
- return single dataframe for `Dumps.collocates()` and `.keywords()` (closes 65)
- paths to directories now end on `_dir` instead of `_path` (`registry_dir`, `lib_dir,` `data_dir`)
- `Corpus._..._available` → `Corpus.available_...()` (`attributes`, `wordlists`, `macros`)
caching
- speed up collocation and keyword retrieval by caching interim results
maintenance
- update dependencies (do not use `pandas v2.x` for now)
- extend doc strings
- remove Pipfile.lock from repository
- add .flake8 file for ignoring long lines
- add a test showing correct functionality of `keywords()` when using several p-atts (closes 73)
ccc-utils
- remove unsupported packages (R 4.3.1)
- improve usability of concordancing function