Implement initial cloverctl CLI tool

Implement initial cloverctl CLI tool

- Uses client-go package to interface to k8s API and implement
functions as cloverkube package.
- Identifies GKE LB IP for clover-controller for user
- Identifies NodePort port number for clover-controller for user
if environment is local k8s (assumes flannel CNI currently)
- Deploys and deletes clover-collector and clover-controller with
native client-go constructs (currently images are defined with
local registry). Future work will implement other clover services
and Istio components. Uses the clover-system namespace.
- Uses Cobra go package to implement CLI (used in kubectl and
istioctl) using cloverctl <verb> <noun> convention.
- Interfaces to clover-controller to configure clover services
(visibility, IDS ...) within the cluster via REST messaging
- Start visibility (collector) engine using input yaml file or
defaults
- Init, stop and clear (truncate Cassandra tables) visibility
engine or get basic stats.
- Add custom rules to IDS from input yaml file and start/stop
IDS
- Generate jmeter testplan on jmeter-master using input yaml
file. Start tests and output log/results from CLI.
- Specify number of jmeter slaves to initiate tests on from
CLI. Automatically find IP addresses of jmeter slaves within
the k8s cluster.
- Sample yaml files for adding IDS rules, starting visibility
engine and generating jmeter test plans.
- Build script to install go and get dependent packages.
- Implement a custom Istio inject package for manual sidecar
injection (cloverinject). Currently, unused as it is built from
Istio 0.8.0/1.0.0 code base.

Change-Id: Ibb8d08cb98267bdffb8905c221473f177d51bbb3
Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>