feat(settings): serializable settings for MQTT broker configuration

Added a class to store MQTT broker settings.

.github/ISSUE_TEMPLATE/issue-template.md

@@ -12,7 +12,7 @@ about: Generic template for issues
 
 ### Environment
 >Please specify:
-> * version of AsImpL (Github master commit hash or at least date/hour when you downloaded it)
+> * version of M2MqttUnity (Github master commit hash or at least date/hour when you downloaded it)
 > * version of Unity3D (e.g. Unity 5.4.4f1)
 
 ### Steps to reproduce

Assets/M2MqttUnity/Scripts/BrokerSettings.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Xml.Serialization;
+using UnityEngine;
+
+namespace M2MqttUnity
+{
+    /// <summary>
+    /// Serializable settings for MQTT broker configuration.
+    /// </summary>
+    [Serializable]
+    [XmlType(TypeName = "broker-settings")]
+    public class BrokerSettings
+    {
+        [Tooltip("Address of the host running the broker")]
+        public string host = "localhost";
+
+        [Tooltip("Port used to access the broker")]
+        public int port = 1883;
+
+        [Tooltip("Encrypted access to the broker")]
+        public bool encrypted = false;
+
+        [Tooltip("Optional alternate addresses, used if the previous host is not accessible")]
+        public string[] alternateAddress;
+    }
+}
+