Backend image rendering as plugin (#11966)

* rendering: headless chrome progress

* renderer: minor change

* grpc: version hell

* updated grpc libs

* wip: minor progess

* rendering: new image rendering plugin is starting to work

* feat: now phantomjs works as well and updated alerting to use new rendering service

* refactor: renamed renderer package and service to rendering to make renderer name less confusing (rendering is internal service that handles the renderer plugin now)

* rendering: now render key is passed and render auth is working in plugin mode

* removed unneeded lines from gitignore

* rendering: now plugin mode supports waiting for all panels to complete rendering

* fix: LastSeenAt fix for render calls, was not set which causes a lot of updates to Last Seen at during rendering, this should fix sqlite db locked issues in seen in previous releases

* change: changed render tz url parameter to use proper timezone name as chrome does not handle UTC offset TZ values

* fix: another update to tz param generation

* renderer: added http mode to renderer service, new ini setting [rendering] server_url

vendor/github.com/aws/aws-sdk-go/private/protocol/query/build.go

@@ -25,7 +25,7 @@ func Build(r *request.Request) {
 		return
 	}
 
-	if r.ExpireTime == 0 {
+	if !r.IsPresigned() {
 		r.HTTPRequest.Method = "POST"
 		r.HTTPRequest.Header.Set("Content-Type", "application/x-www-form-urlencoded; charset=utf-8")
 		r.SetBufferBody([]byte(body.Encode()))