Remove references to standardcado (and close standardcado and develop)

We decided that the standardcado branch was good enough, so it is merged into develop and master, so it can be removed.

The develop branch does not add much to our workflow, so can be removed. We can reintroduce it later if we deem it useful again.

However, there are still references to the standardcado (and perhaps develop) branches, so these need to be removed.