Add kerberos authentication requester using requests_kerberos
Add kerberos authentication requester using requests_kerberos

JohnLZeller/jenkinsapi,zaro0508/jenkinsapi,aerickson/jenkinsapi,JohnLZeller/jenkinsapi,zaro0508/jenkinsapi,mistermocha/jenkinsapi,jduan/jenkinsapi,JohnLZeller/jenkinsapi,salimfadhley/jenkinsapi,domenkozar/jenkinsapi,imsardine/jenkinsapi,domenkozar/jenkinsapi,imsardine/jenkinsapi,jduan/jenkinsapi,imsardine/jenkinsapi,aerickson/jenkinsapi,salimfadhley/jenkinsapi,zaro0508/jenkinsapi,mistermocha/jenkinsapi,mistermocha/jenkinsapi