Copyright notices on the website

This issue is double (or even threefold).

First of all, we have content on our website from third parties. Secondly we have our own content (texts, articles, own pictures...).

Currently I don't see a clear copyright notice for the third-party stuff, neither do I see a copyright notice for our own stuff. AFAIK not adding a copyright notice does not put it in public domain, instead the work should be considered copyrighted and All Rights Reserved. The latter goes against the very core of what we believe in and what made the Pirateparty in the first place. This also brings up a third point: under what licences do we accept third-party stuff on our website.

From this the following questions/proposals follow

1. How do we handle copyright of third party content?
   An example is the flute-playing GNU-logo. This is released under the GPL and GFDL[1], however we do not attribute, we do not give license info, nor do I think we'd be easily able to give the source-code if someone would ask. AFAIK these are violations of the terms!
   One option I see is to have a separate page where we list the exceptions to the general copyright that we would use on the site. On that page we can also give proper attribution and other info/links where needed.

2. What license do we release our own stuff under?
   The wiki has the notice for the WTFPL, which is a very permissive license. Personally I would rather go with a copyleft license like CC BY-SA 4.0 (note that ATM I am talking about the website here, not about changing the license on the wiki).

3. What licenses do we accept for third party content on our website?
   I would say that we should always strive for Free Cultural Licenses[2], preferably copyleft. I think others like Non-commercial, non-derivative, "All Rights Reserved"... should be avoided. We must not violate copyright terms.
   Note that this also implies that people who make things for the website can also ask for attribution instead of attributing it to the Pirateparty.

So I propose
1. Create a separate page for the exceptions (unless anyone else has a better way)
2. License the content of our own site under CC BY-SA 4.0
3. Document some where that
1. We should always strive for Free Cultural Licenses[2], preferably copyleft.
2. Non -Free Cultural Licenses should be avoided. These include, but are not limited to Non-commercial, non-derivative, "All Rights Reserved".
3. We must not violate copyright terms.
4. People who create things for the Pirateparty website can ask for attribution instead of attributing it to the Pirateparty.

Extra
* Where the information from proposal 3 should be documented is still an open question.
* Proposal 3 is purely about the website for the moment, I would like to expand this to the whole PPBE, but that is out of scope for this proposal.

[1] https://www.gnu.org/graphics/meditate.en.html
[2] https://freedomdefined.org/Definition

EDIT: short description of the CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0/