We now track the `config_tls_refresh`, `distributed_interval` and
`logger_tls_period` flag values for each host. Each value is updated by a
detail query agains the `osquery_flags` table, because they may be specified
outside of Kolide. The flags that can be specified within Kolide are also
updated when a config is returned to the host that changes their value.
This will enable us to do a more accurate per-host online status calculation as
discussed in #1419.
Push the calculation of target counts into the SQL query, rather than loading
all of the targets and then counting them. This provides a dramatic (>100x)
speedup in loading of the manage packs page when large numbers of hosts are
present.
Closes#1426
* Change email functionality
* Code review changes for @groob
* Name change per @groob
* Code review changes per @marpaia
Also added addition non-happy path tests to satisfy concerns by @groob