REL: Release 0.9.1

CHANGELOG.md

CITATION.cff

setup.cfg

src/caoscrawler/crawl.py

src/caoscrawler/exceptions.py

src/caoscrawler/sync_node.py

src/doc/conf.py

unittests/test_crawler.py

unittests/test_sync_graph.py

unittests/test_sync_node.py