Confusing error response when posting CSR with windows line breaks

[niligulmohar]

When posting a CSR whose PEM-representation uses windows line breaks instead of unix line breaks, caramel will reject it with status 400 and an error message of "invalid PEM reqtext".

This is reasonable, since the format of the request will affect its hash and therefore its uniqueness, but the error message should be more descriptive.

The exact condition that must be met is that the PEM data of the CSR as generated by OpenSSL must be identical to the one provided in the post.