Added pstn prefix setting

blink/configuration/account.py

@@ -14,6 +14,7 @@ from blink.configuration.datatypes import ApplicationDataPath, CustomSoundFile,
 
 class PSTNSettingsExtension(PSTNSettings):
     idd_prefix = Setting(type=unicode, default=None, nillable=True)
+    prefix = Setting(type=unicode, default=None, nillable=True)
 
 
 class RTPSettingsExtension(RTPSettings):

blink/sessions.py

@@ -1810,6 +1810,8 @@ class SessionManager(object):
             address = cls.number_strip_re.sub('', address)
             if isinstance(account, Account) and account.pstn.idd_prefix is not None:
                 address = re.sub(r'^\+', account.pstn.idd_prefix, address)
+            if isinstance(account, Account) and account.pstn.prefix is not None:
+                address = account.pstn.prefix + address
         return address
 
     def _remove_session(self, session):