Initial service skeleton

Closes #1 (closed)

FYI @valentin.yordanov

cmd/svdx/main.go

+package main
+
+func main() {
+	// load config from file
+
+	// create logger
+
+	// create service and http handler
+
+	// initialize data storage
+
+	// start smtp listener
+
+	// start http listener
+}