Connected clients admin API (#217)

* Add support for ending the inbound stream. Closes #191

* Add a simple success response to API requests

* Connected clients API with geo details

* Post-rebase cleanup

* Make setting and reading geo details separate operations to unblock and speed up

* Rename file

* Fire geoip api call behind goroutine

* Add comment

* Post-rebase fixes

* Add support for the MaxMind GeoLite2 GeoIP database

controllers/connectedClients.go

@@ -0,0 +1,16 @@
+package controllers
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/owncast/owncast/core"
+)
+
+// GetConnectedClients returns currently connected clients
+func GetConnectedClients(w http.ResponseWriter, r *http.Request) {
+	clients := core.GetClients()
+	w.Header().Set("Content-Type", "application/json")
+
+	json.NewEncoder(w).Encode(clients)
+}