Shuffle RESTful URL's around.

This patch moves the RESTful URL's around to more appropriate
locations for release.

The /stasis URL's are moved to /ari, since Asterisk REST Interface was
a more appropriate name than Stasis-HTTP. (Most of the code still has
stasis_http references, but they will be cleaned up after there are no
more outstanding branches that would have merge conflicts with such a
change).

A larger change was moving the ARI events WebSocket off of the shared
/ws URL to its permanent home on /ari/events. The Swagger code
generator was extended to handle "upgrade: websocket" and
"websocketProtocol:" attributes on an operation.

The WebSocket module was modified to better handle WebSocket servers
that have a single registered protocol handler. If a client
connections does not specify the Sec-WebSocket-Protocol header, and
the server has a single protocol handler registered, the WebSocket
server will go ahead and accept the client for that subprotocol.

(closes issue ASTERISK-21857)
Review: https://reviewboard.asterisk.org/r/2621/



git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@393528 65c4cc65-6c06-0410-ace0-fbb531ad65f3

rest-api/api-docs/events.json

@@ -13,6 +13,8 @@
 			"operations": [
 				{
 					"httpMethod": "GET",
+					"upgrade": "websocket",
+					"websocketProtocol": "ari",
 					"summary": "WebSocket connection for events.",
 					"nickname": "eventWebsocket",
 					"responseClass": "Event",
@@ -24,19 +26,6 @@
 							"required": true,
 							"allowMultiple": true,
 							"dataType": "string"
-						},
-						{
-							"name": "Upgrade",
-							"description": "RFC6455 header for upgrading a connection to a websocket.",
-							"paramType": "header",
-							"required": true,
-							"dataType": "string",
-							"allowableValues": {
-								"valueType": "LIST",
-								"values": [
-									"websocket"
-								]
-							}
 						}
 					]
 				}