Redirect some print statments to stderr

Otherwise they errors will not show up if the console output is
redirected to a file

gajim/common/i18n.py

@@ -163,7 +163,7 @@ def ngettext(s_sing, s_plural, n, replace_sing=None, replace_plural=None):
 try:
     locale.setlocale(locale.LC_ALL, '')
 except locale.Error as error:
-    print(error)
+    print(error, file=sys.stderr)
 
 try:
     LANG = get_default_lang()
@@ -172,7 +172,7 @@ try:
         # find the translation
         os.environ['LANG'] = LANG
 except Exception as error:
-    print('Failed to determine default language')
+    print('Failed to determine default language', file=sys.stderr)
     import traceback
     traceback.print_exc()
 
@@ -188,6 +188,6 @@ for dir_ in iter_locale_dirs():
     else:
         break
 else:
-    print('No translations found')
-    print('Dirs searched: %s' % get_locale_dirs())
+    print('No translations found', file=sys.stderr)
+    print('Dirs searched: %s' % get_locale_dirs(), file=sys.stderr)
     _ = _translation.gettext

gajim/common/logging_helpers.py

@@ -28,7 +28,7 @@ def parseLogLevel(arg):
         return int(arg)
     if arg.isupper() and hasattr(logging, arg):
         return getattr(logging, arg)
-    print(_('%s is not a valid loglevel') % repr(arg))
+    print(_('%s is not a valid loglevel') % repr(arg), file=sys.stderr)
     return 0
 
 def parseLogTarget(arg):
@@ -69,7 +69,8 @@ def parseAndSetLogLevels(arg):
             target = parseLogTarget(target.strip())
             if target:
                 logging.getLogger(target).setLevel(level)
-                print("Logger %s level set to %d" % (target, level))
+                print("Logger %s level set to %d" % (target, level),
+                      file=sys.stderr)
 
 
 class colors:

gajim/gtk/exception.py

@@ -80,7 +80,7 @@ class ExceptionDialog():
         traceback.print_exception(type_, value, tb, None, trace)
         self.text = self.get_issue_text(trace.getvalue())
         buffer_.set_text(self.text)
-        print(self.text)
+        print(self.text, file=sys.stderr)
 
         self._ui.exception_view.set_editable(False)
         self._ui.exception_dialog.show()