Modification of judgments prior to March 9, 1955, §19-6-25. Permanent alimony, §§19-6-4 to 19-6-8. Agreement for support as bar to, §19-6-8. Cohabitation grounds for revision, §§19-6-18, 19-6-19. Factors in determining amount, §19-6-5. Foreign divorce decrees, §19-6-27.