- execute native ua call functions in re thread in order to avoid crash when

call ends
- cleaned some code
- upgraded build gradle version

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

@@ -5,6 +5,5 @@ object Api {
     external fun audio_codecs(): String
     external fun call_peeruri(callp: String): String
     external fun cmd_exec(cmd: String): Int
-    external fun uri_decode(uri: String): Boolean
 
-}
+}