Changed the message line of RouterInUse class

Implements: Changed the message line of RouterInUse class,
so user will not get confused with active or inactive ports
while deleting the router.

Closes-Bug: #1236372
Change-Id: I7a82550e2c6051f9e4940a8f1dd4401059e0a8d8
Use os.uname() instead of calling uname in subprocess

Related-Bug: #1291535

Change-Id: I57e18c0b95904f318e3fff08cd18b32e28f48834
Merge "Use os.uname() instead of calling uname in subprocess"
Merge "Changed the message line of RouterInUse class"