Add per-user groups

The security model for PFS is a common one:

• All development and installation work is done by individual user accounts
• All user accounts are also in a common group (pfs)
• All work is saved in a shared directory (/software)

A time-tested way to make that work smoothly is:

• Each user has a primary per-user group id.
• All users are additionally in group pfs
• Each user's $HOME has that group id, and is 0755, so that ssh works safely.
• All shared directories (/software and under) are group pfs and g+srwx.

I notice that the LDAP accounts do not have per-user primary groups. Can they be added?