For performing an action that requires confirmation

tf: Bump Nomad to 0.8.1, Hadoop to 2.7.6

HCL to JSON api endpoint

B 2117 windows group process

Improve help text when invalid arguments are given

[Post-0.8] test: build with mock_driver by default

tests: fix race in alloc_runner_test.go

`make release` and `make prerelease` set a `release` tag to disable
enabling the `mock_driver`

Document job telemetry from #3467

Typo fix on a link

Fix typos in example commands

I could not reproduce the failure locally even with `stress -cpu ...`
eating all the cpu it could on my machine.

But I think the race was in one of two places:
* The task could restart which could create new events
* I think there could be a race between the updater's version of events
  and alloc runners as updates are async

I fixed both. Here's hoping that fixes this flaky test.

UI: Fix a couple flaky tests

This is now necessary in mirage 0.4

Somehow this controller code runs sometimes when the existing jobs
are dematerializing. This makes this.get('model') and array of null