Update stats

[subfuzion]

#12
#87 was submitted by @freignat91. This PR provides a clean rebase with master, completes the process of renaming stat to stats, and performs minor formatting cleanup.

Features

• current cpu, mem, io, net stats on containers, services, tasks, nodes
• -f for streaming on all current stats (using @chrisccoy' single query idea and @subfuzion's coded group-by idea)
• historic and streaming on historic

Verification

amp stats --container
Display containers list with cpu, mem, io, net

amp stats --container -f
Display containers list with cpu, mem, io, net, streaming mode

amp stats --service -f
Display service list with cpu, mem, io, net, streaming mode
(then cpu%, mem% could be greater then 100% in multi nodes env)

amp stats --container --service-name=kafka -f
Display kafka containers list with cpu, mem, io, net, streaming mode

amp stats --task --service-name=kafka -f
Display kafka task list with cpu, mem, io, net

amp stats --task --cpu --mem
Display kafka task list with only cpu, mem

amp stats --node
Display nodes list with cpu, mem, io, net

amp stats --service --service-name=kafka --period 10m -f
Display service kafka cpu, mem, io, net historic from 10 minutes and stream for new data

amp stats --node --period 10m
Display nodes cpu, mem, io, net historic from 10 minutes

All of the following combinations work:

--cpu --mem --io --net
--container --task --service --node
filters:
--service-name --service-id
--task-name --taks-id
--container-id --container-name
--node-id
--datacenter --host

For historic:

-- since --until
--period

[chrisccoy]

👍
Excellent work @subfuzion @freignat91