archive private information from SVN

a common problem in the internal and corp SVN repository shutdown is "what do we do with all that stuff now". for example, the internal repository is shutdown now (#15949 (closed)) but there is still information there that is valuable. or not. we're not sure. we think so, but maybe some of it should be destroyed.

so we need to answer the following questions:

1. which data should be kept and destroyed from the repositories?
2. where should it be kept?

so far, I went under the assertion that the answers were:

1. keep everything
2. in nextcloud

but it seems this might not be exactly right.