Extend the 'network settings' section with indication on the

Extend the 'network settings' section with indication on the
localnet settings (requires the change in SVN 76034), and also
give an indication on whether/why/how the remapping of addresses
in SIP message is done or not.

I think this is especially useful for debugging the configuration,
as the address remapping depends on a combination of at least 3
parameters (localnet, externhost, externip) and successful DNS lookup.

An example of the output of this section is below:

	Network Settings:
	---------------------------
	  SIP address remapping:  Enabled using externhost
	  Externhost:             foo.dyndns.net
	  Externip:               80.64.128.23:0
	  Externrefresh:          10
	  Internal IP:            12.34.56.78:5060
	  Localnet:               192.168.0.0/255.255.0.0
				  10.0.0.0/255.0.0.0

I leave to the community the judgement if the above info is a
useful addition for 1.4. It is not a bugfix, but it is neither a
new feature, only a useful diagnostic tool.

Note that I would like to move there also the bindaddress/port
information, in the usual addr:port format e.g.

          Bindaddress:            0.0.0.0:5060

so that network information is all in one place.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@76035 65c4cc65-6c06-0410-ace0-fbb531ad65f3