Add error reporting during JSON Schema parsing

:Release Notes:
Implemented detailed error reporting during schema parsing.

:Detailed Notes:

:Testing Performed:
Unit tests with memcheck

:QA Notes:

:Issues Addressed:
[ANG-301] pbnjson: Provide more detailed error reporting during schema
          parsing

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

Change-Id: Icfaed82b422311dccc7882a56fc5d01d0d5661db
Reviewed-on: https://g2g.palm.com/4315
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/4623
Tested-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>