Add function 'next_subset'
Store (and later try to restore) only writable settings
Switch libertinus => libertine
Merge branch 'master' of git.sr.ht:~enricoschumann/neighbours
Suppress colour when run non-interactively
Test if quadprog is available
Fix "permute" neighbourhoods with stepsize > 2
Fix numeric neighbourhood with updating and 'active'
vector, in which case min/max could be ignored.