There are a lot of add-ons in Plone for sliders/banners/teasers.
We thought there should be a better one and created collective.behavior.banner.
To use it add the name to your list of eggs in buildout.cfg:
eggs= Plone ... collective.behavior.banner
Even though collective.behavior.banner has been released on PyPI we will now act as if this add-on exists on GitHub or has changes on GitHub that have not yet been released, but that you really want.
This is not to annoy you.
It happens surprisingly often if you work with new versions of Plone.
The training buildout has a section [sources] that tells buildout to download a specific add-on not from PyPI but from some code repository (usually GitHub):