certprofile: add option to export profile config

Add the `--out=FILENAME' option to `certprofile-show'.  When given,
it exports the profile configuration from Dogtag and writes it to
the named file.

Fixes: https://fedorahosted.org/freeipa/ticket/5091
Reviewed-By: Martin Basti <mbasti@redhat.com>

ipaserver/plugins/dogtag.py

@@ -2081,6 +2081,14 @@ class ra_certprofile(RestClient):
             body=profile_data
         )
 
+    def read_profile(self, profile_id):
+        """
+        Read the profile configuration from Dogtag
+        """
+        status, status_text, resp_headers, resp_body = self._ssldo(
+            'GET', profile_id + '/raw')
+        return resp_body
+
     def enable_profile(self, profile_id):
         """
         Enable the profile in Dogtag