NOTES

TODO:
[ ] Add system.performance.get to A10LoadBalancer
[ ] Add tests

DONE:
[X] Replace "--host HOST" with "--slb-host HOST[:PORT]", thread the port through
    A10LoadBalancer and A10RestApi, and only set SSL options on the Net::HTTP
    object if using port 443, or if --use-ssl option is included.
[X] Write collect_a10_metrics.rb
[X] Move common data-fetching code to new class (eg. `A10LoadBalancer`)
    [X] Update check_a10_vserver
    [X] Pass sleep_seconds in check_a10_vserver_bw, check_a10_link_bw
    [-] Add verbose output to check_a10_vserver_bw
    [X] Do not sleep during check_a10_vserver (don't need rate info)
[X] Convert all hash keys from strings to symbols, or to OpenStruct
[X] virtual_server, service_group, network.interface (and virtual_service) all
    have both config data and stats data. Expose both. Is there a better way
    to organize this data (ie. embed stats within overall config data)?
    - Have both #get_foo_stats and #get_foo_config methods
    - Make sure the hashes are keyed off of the object names, for easy lookup
    - Make sure port data hashes are keyed off port numbers, for easy lookup
[X] Handle broken pipe in query_a10_api.rb
[X] Add version