Fix missing syslog items in config schema [JIRA: RCS-212]

[ksauzz]

Riak CS fails due to missing syslog configs if one attempt to enable syslog by log.syslog=on in riak-cs.conf.

This PR also includes a small refactoring commit on tests.

Error messages

% bin/riak-cs console
19:26:45.918 [error] Error generating configuration in phase apply_translations
19:26:45.918 [error] Translation for 'lager.handlers' expected to find setting 'log.syslog.ident' but was missing
Error generating config with cuttlefish
  run `riak-cs config generate -l debug` for more information.

[kuenishi]

@ksauzz Good catch. Could you write down here the workaround you showed in the customer ticket?

[ksauzz]

Workaround

Add lager configs into advanced.config including lager_syslog_backend like:

 {lager, [
          {handlers, [
                      {lager_syslog_backend, ["riak", local1, info]},
                      {lager_console_backend, info},
                      {lager_file_backend, [{file, "/var/log/riak-cs/error.log"},
                                            {level, error},
                                            {size, 10485760},
                                            {date, "$D0"},
                                            {count, 5}]},
                      {lager_file_backend, [{file, "/var/log/riak-cs/console.log"},
                                            {level, info},
                                            {size, 10485760},
                                            {date, "$D0"},
                                            {count, 5}]}
                     ]}
         ]},

app.config in Riak CS 1.5.x is a good example to set lager configs in advanced.config.

[kuenishi]

Ah, yes. Copy and pasting from 1.5 app.config is the best way.

[kuenishi]

@ksauzz Could you back port this to 2.0 branch as well? I think this is worth being backported.

[kuenishi]

@Basho-JIRA open a ticket for this

[kuenishi]

[ksauzz]

@kuenishi Will do.

[kuenishi]

@borshop merge

[Basho-JIRA]

Will also be backported to 2.0.

_[posted via JIRA by Kota Uenishi]_

[kuenishi]

@borshop merge

[Basho-JIRA]

Release note: Fix a configuration system bug where Riak CS could not start if log.syslog=on is set. See original pull request for workaround in 2.0.x.

_[posted via JIRA by Kota Uenishi]_