[demo-express] Move usecase to demo-express

- Move usecase to demo-express
- Failure analysis: https://crosswalk-project.org/jira/browse/XWALK-1954
                    https://crosswalk-project.org/jira/browse/XWALK-1266

Impacted tests(approved): new 0, update 4, delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: pass 2, fail 2, block 0
better improve it as: This sample demonstrates the NBS with network connect and release operations.