dev-python/bokeh: dev-python/bokeh: Copy latest ebuild from portage

Package-Manager: portage-2.2.10
dev-python/bokeh: dev-python/bokeh: New version with python3 support for bug #516052

Package-Manager: portage-2.2.10
Merge pull request #237 from aufau/bokeh

dev-python/bokeh (in the main tree): Fix bug #516052