Add auth_pid_filetrans_pam_var_run

This interface allows a domain to create resources inside the generic
pid location (/var/run) and have them created with the pam_var_run_t
type.
Allow sudo to create /var/run/sudo if non-existing

When sudo is invoked and the /var/run/sudo directory (in which a ts/
subdirectory would be created and managed by sudo) is not available yet,
sudo will try to create it.

Grant it this privilege and have this directory be labeled as
pam_var_run_t.

Without this, we get:
sudo: unable to mkdir /var/run/sudo: Permission denied
Allow setting ownership of ts/ directory

When creating the ts/ directory (in which sudo keeps timestamps), allow
the sudo application to set ownership.

No errors involved (only denial) but the end result is different (group
ownership is different, even though there is no group privilege).