release: ready to release v1.6.1

release: ready to release v1.6.0

release: ready to release v1.5.0

release: ready to release v1.4.1

release: ready to release v1.4.0

release: ready to release v1.3.0

update version to v1.2.0

change version

remove cairo dependency in docs

Merge pull request #1284 from niedong/typo-fix

fix typo docstring in scene_file_writer.py