added graphical account configuration and many other improvements

app/src/main/kotlin/com/tutpro/baresip/UserAgent.kt

@@ -0,0 +1,35 @@
+package com.tutpro.baresip
+
+class UserAgent (val uap: String) {
+
+    val account = Account(ua_account(uap))
+    val aor = ua_aor(uap)
+
+    companion object {
+
+        external fun ua_alloc(uri: String): Int
+        external fun ua_destroy(uri: String)
+        external fun ua_register(ua: String): Int
+        external fun ua_isregistered(ua: String): Boolean
+        external fun ua_unregister(ua: String)
+
+        fun userAgents(): ArrayList<UserAgent> {
+            val res = ArrayList<UserAgent>()
+            for (ua in MainActivity.uas) {
+                res.add(ua)
+            }
+            return res
+        }
+
+        fun find(uas: ArrayList<UserAgent>, uap: String): UserAgent? {
+            for (u in uas) {
+                if (u.uap == uap) return u
+            }
+            return null
+        }
+    }
+}
+
+external fun ua_account(ua: String): String
+external fun ua_aor(ua: String): String
+