Added possibility to set SMTP port.

src/config.rs

@@ -65,6 +65,7 @@ pub struct Mailing {
     from: String,
     path: Option<String>,
     server: Option<String>,
+    port: Option<u16>,
     user: Option<String>,
     password: Option<String>,
     tls: Option<bool>
@@ -84,6 +85,9 @@ impl Mailing {
     pub fn server(&self) -> &Option<String> {
         &self.server
     }
+    pub fn port(&self) -> Option<u16> {
+        self.port
+    }
     pub fn user(&self) -> &Option<String> {
         &self.user
     }