Upgrade favicon to use small-format logos
Make logo linked as well as text
Add breadcrumb navigation to the top of every page

We discussed that this would make it easier to find their way around
deeply nested parts of the site. Obviously we should probably eliminate
these deeply nested parts of the site over time, but at least for now,
having some breadcrumbs is better than not having any.
Add ability to set background images for page banners
style: Ensure correct padding at top of content
Shorten over-long lines in djangocms_pagebanner
style: Ensure correct padding (continuing 72cc6ea)
organisation: Add a project list plugin

This commit adds a CMS plugin that can be used to display a list of
projects in, say, a sidebar, optionally filtered by theme and project
type.
Merge remote-tracking branch 'origin/master' into networkgroups

Conflicts:
	foundation/organisation/cms_plugins.py
	foundation/organisation/tests/test_cms_plugins.py

Migration fixed as well to keep sequence.