Implement initial Jmeter master/slave containers

Implement initial Jmeter master/slave containers

- Jmeter can be used for L4-7 functional and performance testing
- Jmeter master has gRPC server for management
- Generates Jmeter test plans from minimal yaml params file
(sample to be added with cloverctl) using template
- Optionally span tests across slave containers to allow greater
loads to be generated
- Specify loop/thread/slave count and URL list, which
dictates target and number of connections that will be attempted
- clover-controller will interface to gRPC interface on Jmeter
master
- Start tests on master and retrieve log/result files
- Render master and slave k8s manifests files

Change-Id: Id144c8f551b7d375ff252c8de0611f895b50387c
Signed-off-by: Eddie Arrage <eddie.arrage@huawei.com>