Minor patch

when I prepared 3rd milestone, I fixed some parts.
*  Increase timeout in listener proxy
In case of using low spec device (ex. nexus 10/ Lollipop), Concert checker occasionally returned ```MasterInfo``` message does not receive error. Because low spec device is not enough 4s for receiving message.

*  Addition of Exception handling in onStart function of MasterInfo class.
The android app using MasterInfo class for checking concert is died if it run in only launched roscore.