Many thanks to @iverberk for the original PR (#1609), but we ended up
not wanting to ship this implementation with 0.5.
We'll come back to it after 0.5 and hopefully find a way to leverage
filesystem accounting and quotas, so we can skip the expensive polling.
When alloc-status is called, in it's long form only, print the resource
utilization for that single allocation.
When node-status is called, in it's long form only, print the TOTAL
resource utilization that is occurring on that single node.
Nomad Alloc Status:
```
% nomad alloc-status 195d3bf2
ID = 195d3bf2
Eval ID = c917e3ee
Name = example.cache[1]
Node ID = 1b2520a7
Job ID = example
Client Status = running
Evaluated Nodes = 1
Filtered Nodes = 0
Exhausted Nodes = 0
Allocation Time = 17.73µs
Failures = 0
==> Task "redis" is "running"
Recent Events:
Time Type Description
04/03/16 21:20:45 EST Started Task started by client
04/03/16 21:20:42 EST Received Task received by client
==> Status
Allocation "195d3bf2" status "running" (0/1 nodes filtered)
* Score "1b2520a7-6714-e78d-a8f7-68467dda6db7.binpack" = 1.209464
* Score "1b2520a7-6714-e78d-a8f7-68467dda6db7.job-anti-affinity" = -10.000000
==> Resources
CPU MemoryMB DiskMB IOPS
500 256 300 0
```
Nomad Node Status:
```
% nomad node-status 57b3a55a
ID = 57b3a55a
Name = biscuits
Class = <none>
DC = dc1
Drain = false
Status = ready
Attributes = arch:amd64, cpu.frequency:3753.458875, cpu.modelname:Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz, cpu.numcores:8, cpu.totalcompute:30027.671000, driver.docker:1, driver.docker.version:1.10.2, driver.exec:1, driver.raw_exec:1, hostname:biscuits, kernel.name:linux, kernel.version:4.4.0-9-generic, memory.totalbytes:25208934400, os.name:ubuntu, os.version:16.04, unique.cgroup.mountpoint:/sys/fs/cgroup, unique.network.ip-address:127.0.0.1, unique.storage.bytesfree:219781419008, unique.storage.bytestotal:246059892736, unique.storage.volume:/dev/sdb3
==> Allocations
ID Eval ID Job ID Task Group Desired Status Client Status
2c236883 aa11aca8 example cache run running
32f6e3d6 aa11aca8 example cache run running
==> Resource Utilization
CPU MemoryMB DiskMB IOPS
1000 512 600 0
```
