Add Core-Command Testcases

[cherrycl]

Signed-off-by: Cherry Wang cherry@iotechsys.com Add the following test cases for core-command. Total 7 testcases.

• Get all devices command at once (50 devices)
  • Once / per 5 secs continuously around 1 hour
• Get 50 devices command by name/id concurrently
  • Once / per 5 secs continuously around 1 hour
• Put 50 devices adminstate command by name/id concurrently
  • Once / per 5 secs continuously around 1 hour
• Put 50 devices opstate command by name/id concurrently
  • Once / per 5 secs continuously around 1 hour