Improve comment and error message in ctfe/handlers.go
Improve comment and error message in ctfe/handlers.go

google/certificate-transparency-go,daviddrysdale/certificate-transparency-go,daviddrysdale/certificate-transparency-go,RJPercival/certificate-transparency-go,daviddrysdale/certificate-transparency-go,google/certificate-transparency-go,RJPercival/certificate-transparency-go,google/certificate-transparency-go,RJPercival/certificate-transparency-go