refactor: Make a skeleton of main.go (openkeepd binary)

.gitignore

@@ -10,3 +10,4 @@
 
 # Output of the go coverage tool, specifically when used with LiteIDE
 *.out
+/openkeepd

cmd/openkeepd/main.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/sirupsen/logrus"
+)
+
+var logger = logrus.New()
+
+func main() {
+	logger.Info("Starting openkeepd server...")
+
+	logger.Info("Server successfully started!")
+
+	// CTRL+C handler.
+	signalHandler := make(chan os.Signal, 1)
+	shutdownDone := make(chan bool, 1)
+	signal.Notify(signalHandler, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		<-signalHandler
+		logger.Info("CTRL+C or SIGTERM received, shutting down openkeepd...")
+		shutdownDone <- true
+	}()
+
+	<-shutdownDone
+	logger.Info("Server successfully shutted down")
+	os.Exit(0)
+}