added account_[set_]sipnat API functions

added ua_update_account API function
go directly to settings of new account
fixed some main activity layout bugs
keep main activity interactive when screen is locked
removed aor from UserAgent class
added register method to UserAgent class
added foregrounded and isDeviceLocked util functions
updated libbaresip distribution

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

@@ -36,13 +36,8 @@ class Call(val callp: String, val ua: UserAgent, val peerURI: String, val dir: S
             return null
         }
 
-        fun index(calls: ArrayList<Call>, call: Call, dir: String): Int {
-            var res = 0
-            for (c in calls) {
-                if (c == call) return res
-                if ((dir == "") || (call.dir == dir)) res++
-            }
-            return res
+        fun uaCallIndex(calls: ArrayList<Call>, ua: UserAgent, call: Call, dir: String): Int {
+            return uaCalls(calls, ua, dir).indexOf(call)
         }
 
     }