Rape-Penal Code section 113—evidence of carnal knowledge—unsatisfactory evidence of complainant regarding absence of consent or consent obtained by force or intimidation—absence of corroboration on a charge of rape not essential in law but usually required—alternative charge of procuring defilement of woman by threats or intimidation—Penal Code section 122 (1)—latter section makes corroboration in some material particular necessary to support conviction on such alternative charge.