In prosecutions for the crime of rape, evidence of the prosecuting witness’ previous sexual conduct shall not be admitted nor reference made thereto in the presence of the jury, except as provided hereinafter. The defendant may make application to the court before or during the trial for the admission of evidence concerning the previous sexual conduct of the prosecuting witness. Upon such application the court shall conduct a hearing out of the presence of the jury as to the relevancy of such evidence of previous sexual conduct and shall limit the questioning and control the admission and exclusion of evidence upon trial. Nothing in this section shall limit the right of either the state or the accused to impeach credibility by the showing of prior felony convictions.