Bugfix release

What's Changed

• fix iw.set_data by @kushalkolar in #851
• add github button to docs by @kushalkolar in #845
• retry sklearn datset downloads if 403 error by @kushalkolar in #844
• Update docstrings by @kushalkolar in #841
• remove Graphic.share_property() and unshare_property() by @kushalkolar in #842
• better docs on use in jupyterlab and ipython by @kushalkolar in #843
• fix move to pointer for linear and linear region selector by @kushalkolar in #855
• Imgui pin to attempt bugfix release by @kushalkolar in #876

Full Changelog: v0.5.0...v0.5.1