add a new argument to PrivacyManager to specify a context

where the entered phone number is checked.

You can now define a set of extensions/exten patterns that describe
valid phone numbers. PrivacyManager will check that context for a match
with the given phone number.
This way you get better control. For example people blindly hitting
10 digits just to get past privacymanager

Example line in extensions.conf:
exten => incoming,n,PrivacyManager(3,10,,route-outgoing)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@121197 65c4cc65-6c06-0410-ace0-fbb531ad65f3