ARI: Retrieve existing log channels

An http request can be sent to get the existing Asterisk logs.

The command "curl -v -u user:pass -X GET 'http://localhost:8088
/ari/asterisk/logging'" can be run in the terminal to access the
newly implemented functionality.

* Retrieve all existing log channels

ASTERISK-25252

Change-Id: I7bb08b93e3b938c991f3f56cc5d188654768a808

rest-api/api-docs/asterisk.json

@@ -296,6 +296,18 @@
 				}
 			]
 		},
+		{
+			"path": "/asterisk/logging",
+			"description": "Asterisk log channels",
+			"operations": [
+				{
+					"httpMethod": "GET",
+					"summary": "Gets Asterisk log channel information.",
+					"nickname": "listLogChannels",
+					"responseClass": "List[LogChannel]"
+				}
+			]
+		},
 		{
 			"path": "/asterisk/logging/{logChannelName}",
 			"description": "Asterisk log channel",