This PR contains a fix for a bug that turned up when I was testing configimporter. If the platform field is not specified, its supposed to default to all per the osquery configuration spec. The default was not properly implemented, and if the platform value was missing from the imported configuration it failed. The PR also added instructions to the api documentation describing how to import an osquery configuration.
* Fix issue where config interval can be number or string
* Implemented @groob code review suggestions
* Added type assertions with graceful failure if something slips through validation
* Implemented code review changes per @zwass