Implement directory specific saving of sort-column and sort-order (#8)

Implements the saving of sort-column and sort-order for each directory.
2 jobs for !19 with per-directory-settings-6 in 6 minutes and 8 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Build
passed #1874
build

00:02:37

 
  Distcheck
passed #1875
distcheck

00:03:31