ENG-2737: Porting nonredundant functionalities of local_cluster_ctl to yb-ctl.

Summary:
This diff ports the nonredundant functionalities of local_cluster_ctl to yb_ctl. These are
the actual functionalities it ports:

1. The addition of --verbose flag.
2. The addition of --use_cassandra_authentication flag(which is tserver only) and set to
false by default.
3. Implementation of wipe-restart. This basically destroys the cluster, deletes the
/tmp/yugabyte-local-cluster directory and then re-starts the cluster with the same number of
masters/tservers as before. At this point of time we do not save state(as in which nodes are running
and which are not, and the gflags passed). Planning to change this later.
4. Implementation of master node addition using add_node --master.
5. Implementation of stop_node(for masters as well as tservers).

Jenkins: skip

Test Plan:
Manually tested by running the scripts for different conditions and verifying that the
behavior is as expected in the UI.

Reviewers: mikhail, karthik, bogdan

Reviewed By: bogdan

Subscribers: sid, bristy, ybase

Differential Revision: https://phabricator.dev.yugabyte.com/D4080

Author: ayushsengupta1991

.arclint

@@ -14,7 +14,7 @@
     },
     "pycodestyle": {
       "type": "pep8",
-      "include": "(\\.py$)",
+      "include": "(\\.py$|yb-ctl$)",
       "exclude": "(^thirdparty/|^[.]ycm_extra_conf[.]py$)",
       "bin": "pycodestyle"
     },