Bug 2968 - SIP ACS_STATUS message (98) misreported config.

Bug 2968 - SIP ACS_STATUS message (98) misreported config.

The *_ok methods in ILS.pm were targeting the wrong depth.
This also resolves a longstanding FIXME on to_bool() warning like:
    Argument "\x{66}\x{61}..." isn't numeric in numeric ne (!=) at /ILS.pm line 94.

The example_institution_dump.sh essentially provides the proof test case for this patch.
Run it before/after on SIPconfig.xml where "MAIN" has checkout="true" and checkin="true".

Signed-off-by: Galen Charlton <galen.charlton@liblime.com>