added changes that brings in a new option with trivup command i.e a daemon flag(--d)

[poushalibanik]

A new option has been added to trivup (--d) that now enables trivup to run in the background. With this change trivup now runs for as long as possible and it won't stop the cluster unless n until someone kills the process explicitly.
The PR has 4 main changes :

1. Added a new daemon option(--d) and its corresponding logic.
2. The new logic now gives us the process id, which can be later on used to kill the process explicitly.
3. Gives us the broker port as output.
4. And also gives us the schema port. (no need of additional steps for fetching schema port)

There's another change as well wherein the url instead of just printing localhost now prints the hostname of the system wherever trivup is being ran.

With option --d alone:

Without option --d:

Option --d along with broker-ports option:

Option --d along with brokers option i.e broker count: