Fix 'integer' type restrictions in JSON Schema

:Release Notes:
Fixed 'integer' type restrictions if number related properties (ex.
'maximum') are provided in JSON Schema

:Detailed Notes:

:Testing Performed:
Unit tests with memcheck.

:QA Notes:

:Issues Addressed:
[ANG-302] pbnjson: 'integer' type restriction doesn't work if number
          properties are provided

Open-webOS-DCO-1.0-Signed-off-by: Mykola Kryvonos <mykola.kryvonos@lge.com>

Change-Id: Id34508a6d9264dc10fe98df470358cf82b85271a
Reviewed-on: https://g2g.palm.com/4277
Reviewed-by: DCO Verification
Reviewed-by: Mykola Kryvonos <mykola.kryvonos@lge.com>
Tested-by: Mykola Kryvonos <mykola.kryvonos@lge.com>
Reviewed-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>
Reviewed-on: https://g2g.palm.com/4621