Add function load_csr(file,format,desc) to apps/lib/apps.c

Add function load_csr(file,format,desc) to apps/lib/apps.c

Make use of new load_csr() in 'ca', 'req', and 'x509' app
Add '-inform' and '-certform' option to 'ca' app
Add 'desc' parameter to load_crl() function defined in apps/lib/apps.c
Allow 'desc' parameter to be NULL (gives option to suppress error output)

Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
Reviewed-by: David von Oheimb <david.von.oheimb@siemens.com>
(Merged from https://github.com/openssl/openssl/pull/4940)