Replace numeric error codes with enums.
Replace numeric error codes with enums.

kariminf/snowball,snowballstem/snowball,kariminf/snowball,snowballstem/snowball,JDemler/snowball,JDemler/snowball,JDemler/snowball,assem-ch/snowball,JDemler/snowball,assem-ch/snowball,assem-ch/snowball,cesarsouza/snowball,cesarsouza/snowball,JDemler/snowball,snowballstem/snowball,cesarsouza/snowball,snowballstem/snowball,cesarsouza/snowball,assem-ch/snowball,cesarsouza/snowball,kariminf/snowball,snowballstem/snowball,kariminf/snowball,snowballstem/snowball,JDemler/snowball,cesarsouza/snowball,assem-ch/snowball,kariminf/snowball,snowballstem/snowball,snowballstem/snowball,cesarsouza/snowball