Richard: You had some ideas about how you want this done, so assigned to you.

> Richard: You had some ideas about how you want this done, so assigned to you.

Basically, balance_pool and the inventory scripts should both use
model only, and never consider the board label.

I have the initial CL here:
    http://crosreview.com/893527

Additionally, a handful of DUTs have anomalous board/model
pairings:

DUT                            Board                Model
chromeos2-row4-rack9-host2     coral                coral
chromeos4-row13-rack2-host12   nyan_kitty           kitty
chromeos4-row10-rack8-host13   auron_yuna           yuna
chromeos4-row9-rack10-host15   veyron_minnie        minnie
chromeos4-row9-rack11-host17   veyron_minnie-cheets veyron_minnie
chromeos4-row8-rack5-host7     auron_paine          paine
chromeos4-row8-rack4-host17    auron_paine          paine
chromeos4-row8-rack5-host12    auron_paine          paine
chromeos4-row8-rack7-host12    terra                terra2
chromeos6-row2-rack11-host14   peach_pit            pit
chromeos2-row4-rack9-host14    coral                coral
chromeos6-row3-rack7-host1     veyron_tiger         tiger
chromeos6-row3-rack7-host11    veyron_tiger         tiger
chromeos6-row4-rack8-host14    veyron_tiger         tiger

The anomalies will be fixed shortly.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromiumos/third_party/autotest/+/5de01eb5e3520284c70a71483fd139fc6ca2e5ef

commit 5de01eb5e3520284c70a71483fd139fc6ca2e5ef
Author: Richard Barnette <jrbarnette@chromium.org>
Date: Thu Feb 08 00:32:32 2018

[autotest] Convert inventory management to be model based

BUG= chromium:798889 
TEST=None

Change-Id: I986ecd424c761d1e4a37568a86707c31569c4e92
Reviewed-on: https://chromium-review.googlesource.com/893527
Tested-by: Richard Barnette <jrbarnette@chromium.org>
Reviewed-by: Richard Barnette <jrbarnette@google.com>

[rename] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/contrib/run-model-inventory
[add] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/contrib/run-board-inventory
[modify] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/contrib/inventory_options
[modify] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/site_utils/lab_inventory.py
[modify] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/site_utils/balance_pools.py
[modify] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/contrib/run-pool-inventory
[modify] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/server/lib/status_history.py
[modify] https://crrev.com/5de01eb5e3520284c70a71483fd139fc6ca2e5ef/site_utils/lab_inventory_unittest.py