HPCC-10108 No way to disable quote processing and use the CSV quick partitioning

Add quote char overriding with zero ('') string capability.
Fix empty quote handling bug in CCsvQuickPartitioner constructor.
Add extra pass to discover record structure into CCsvQuickPartitioner.

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
HPCC-10108 No way to disable quote processing and use the CSV quick
partitioning

Remove changes from CCsvPartitioner constructor.

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>
Merge pull request #4898 from AttilaVamos/HPCC-10108-fix

HPCC-10108 No way to disable quote processing and use the CSV quick partitioning

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>