core: use of Const for profile_key + replaced '@DEFAULT@' default profile_key by '@NONE@'

src/plugins/plugin_exp_pipe.py

@@ -18,6 +18,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from sat.core.i18n import _
+from sat.core.constants import Const as C
 from logging import debug, info, warning, error
 from twisted.words.xish import domish
 from twisted.words.protocols.jabber import jid
@@ -222,7 +223,7 @@ class Exp_Pipe(object):
         else:
             warning(_("Invalid stream method received"))
 
-    def pipeOut(self, to_jid, filepath, data={}, profile_key='@DEFAULT@'):
+    def pipeOut(self, to_jid, filepath, data={}, profile_key=C.PROF_KEY_NONE):
         """send a file using EXP-PIPE
         @to_jid: recipient
         @filepath: absolute path to the named pipe to send