Port missing features from release-7.3 branch

net/asterisk/files/iopsys/etc/config/asterisk

@@ -89,6 +89,7 @@ config outgoing_map 'outgoing_map1'
 	option line 'line0'
 
 config group 'group1'
+	list extensions 'extension1'
 
 config call_filter 'call_filter0'
 	option block_foreign '0'
@@ -183,3 +184,13 @@ config sip_service_provider 'sip0'
 	option encryption '0'
 	option mediasec '0'
 
+config extension 'extension0'
+	option extension_number '0000'
+	option name ''
+	option type ''
+	option enable '1'
+	option calling_features 'set1'
+	option txgain '0'
+	option rxgain '0'
+	option comfort_noise '0'
+	option echo_cancel '1'