check config standalone boolean

[foomatty]

Although it's defined as a boolean

f.puts JSON.pretty_generate(conf) seems to write it out as a string.

[jlambert121]

I tried forcing a json to write a boolean many ways without success. There was some discussion tonight in #sensu about having sensu honor booleans as strings though. That might be the easiest fix for this.

[foomatty]

I guess can just use templates in the meantime.

[phobos182]

I have a PR open to fix this. #43

The fix is to have undef by default. Then supplying true to the aggregate / standalone argument with the fix will apply this correctly to the resulting JSON file. No quotes, no strings.

[jamtur01]

Merged.