ini: Add internal validator allowed_sections
Ticket:
https://fedorahosted.org/sssd/ticket/133
This validator allows to list all sections
that can be used in config file. Sections
can be specified using string or regular
expression.
Format is:
[rule/allowed_sections]
validator = ini_allowed_sections
section = foo
section = bar
section_re = ^baz/.*
Signed-off-by: Lukas Slebodnik <lslebodn@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>