Ingest lnet data from storage servers into management db

[johnsonw]

In addition to collecting network interface information we should also
collect lnet data from lnetctl net show from each storage server. This
information should then be ingested into the database on the manager
through the iml-network service.

Signed-off-by: johnsonw wjohnson@whamcloud.com

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This change is 

[johnsonw]

Sample output from the postgres database after ingesting lnet data from the storage servers:

chroma=> select * from lnet;
 id  |       nid       | host_id | net_type | status | interfaces
-----+-----------------+---------+----------+--------+------------
 751 | 10.73.20.22@tcp |       4 | tcp      | up     | {eth1}
 752 | 10.73.20.21@tcp |       3 | tcp      | up     | {eth1}
 753 | 10.73.20.11@tcp |       1 | tcp      | up     | {eth1}
 754 | 10.73.20.12@tcp |       2 | tcp      | up     | {eth1}

[johnsonw]

Two tables are created and updated according to the lnet data spanning across the storage servers:

1. lnet
2. nid

The nid table contains all of the nid information for a particular host. There will likely be multiple entries for a single host. The lnet table on the other hand, will have a single entry for each host and contain a list of nid id's the correspond to the matching nids for the host in context.

Example output:

chroma=> select * from lnet;
 id | host_id | nids
----+---------+------
  3 |       6 | {6}
  4 |       5 | {1}
  1 |       7 | {7}
  2 |       8 | {8}
(4 rows)

chroma=> select * from nid;
 id | net_type | host_id |       nid       | status | interfaces
----+----------+---------+-----------------+--------+------------
  6 | tcp      |       6 | 10.73.20.12@tcp | up     | {eth1}
  1 | tcp      |       5 | 10.73.20.11@tcp | up     | {eth1}
  7 | tcp      |       7 | 10.73.20.21@tcp | up     | {eth1}
  8 | tcp      |       8 | 10.73.20.22@tcp | up     | {eth1}
(4 rows)

[johnsonw]

As discussed, I added state to the lnet table. Here is the new output:

chroma=> select * from lnet;
 id | host_id | state | nids
----+---------+-------+------
  4 |       4 | up    | {4}
  1 |       2 | up    | {1}
  2 |       1 | up    | {2}
  3 |       3 | up    | {3}
(4 rows)

chroma=> select * from nid;
 id | net_type | host_id |       nid       | status | interfaces
----+----------+---------+-----------------+--------+------------
  4 | tcp      |       4 | 10.73.20.22@tcp | up     | {eth1}
  1 | tcp      |       2 | 10.73.20.12@tcp | up     | {eth1}
  2 | tcp      |       1 | 10.73.20.11@tcp | up     | {eth1}
  3 | tcp      |       3 | 10.73.20.21@tcp | up     | {eth1}
(4 rows)

The base branch was changed.