Revision 1772669

On the ocsp-verification branch: Add support for importing
certificates from their exported form.

* serf_bucket_types.h
  (serf_ssl_cert_import): New prototype ...
* buckets/ssl_buckets.c
  (serf_ssl_cert_import): ... implemented here.

* test/test_ssl.c
  (load_cert_file_der): New; utility function for loading the Base64-
   -encoded certificate from a PEM-encoded file.
  (test_ssl_cert_export): Use load_cert_file_der.
  (test_ssl_cert_import): New test case, for serf_ssl_cert_import.
  (test_ssl): Add test_ssl_cert_import to the test suite.