N-API: Add functions to delete properties

[mhdawson]

• Version: ALL
• Platform: ALL
• Subsystem: N-API

There should be NAPI functions for deleting named properties and indexed properties:

napi_status napi_delete_property(napi_env env, napi_value object, napi_propertyname name);
napi_status napi_delete_element(napi_env env, napi_value object, uint32_t i);

So far only one of the top native modules scanned (couchbase) referenced v8::Object::Delete().

The N-API team will get to this based on priorities, but this is a good place for others to contribute as well. If you start working on this, assign the issue to yourself and add a comment that you are working on it.

[cjihrig]

@mhdawson I'd like to work on this.

[mhdawson]

sounds good :)