released 4.2.1
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Fix ambiguity between Literal(False) and None in Graph.items(...)
Merge pull request #382 from bcogrel/master

Fix ambiguity between Literal(False) and None in Graph.items(...)
test-case for #382
State current version number & give PyPI link

Since the ``README.md`` file serves as the project homepage, this information is useful to add.
Merge pull request #383 from peterjc/patch-1

Current version number &PyPI link in README.md
Test boolean list serialization in Turtle
Fix boolean list serialization in Turtle
Merge pull request #387 from bcogrel/ttl-bool

Bad boolean list serialization to Turtle
tiny doc cleanup