Renaming the project group

The organization that has housed backupninja over the years (Riseup Labs) has officially changed its name to "Liberate". As part of the change in name, it would be good to move the backupninja project out of the 'riseuplabs' group namespace in gitlab to the 'liberate' namespace. The other projects that were housed there have been moved already, but there may be some things that backupninja would need to do to prepare for the move. Maybe we can map out here what are the things that need to be done to make the namechange complete.

The things I can think of are:

• click the button in gitlab to move the project to the new namespace (gitlab will give redirection warnings for web and git remotes)
• change any documentation that might list the riseuplabs namespace
• change debian/control so that the correct website is listed
• update debian/changelog so it lists the right organization and copyright year: https://0xacab.org/riseuplabs/backupninja/-/blob/debian/debian/copyright#L13
• change the reference on liberate.org to point to the new name (its currently pointing to the riseuplabs namespace)