Fixed sonar issues in Split class and refactor it

Removed unnecesary conversion: bouncle castle RDN -> String -> CertService RDN.
Now it's: Bouncle castle RDN -> CertService RDN.
Class Split rewritten on streams, tested.

Signed-off-by: Michal Banka <michal.banka@nokia.com>
Change-Id: I04e10fd6e4ab619124b93db7193c94f54b4b08ef
Issue-ID: AAF-997
4 files changed