confdb: Make it possible to use config snippets
Resolves:
https://fedorahosted.org/sssd/ticket/2247
Signed-off-by: Lukas Slebodnik <lslebodn@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>
Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>