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- Support mmult import from reportlab < 3.5.61 (316).
- Make zero-length Line, PolyLine and Polygon appear in PDFs when their stroke
value is non-zero (319).
- ``<symbol>`` nodes now only appears in documents when they are
referenced, not on their initial appearance (328).
- If only rx or ry is defined on a ``<rect>``, the value is used for both.
- Support non-prefixed ``href`` attribute added in SVG 2 (330).
- Fixed parsing of empty SVG style nodes (325).
- Handle content of multiple SVG style nodes (326).
- Better font caching for some font names (338).