Event struct field naming

[e-dant]

The event structure currently has some very generic field names. From the readme:

The `event` object will contain the:
  - `where`, which is an absolute path to the event.
  - `kind`, the kind of path. One of:
    - `dir`
    - `file`
    - `hard_link`
    - `sym_link`
    - `watcher`
    - `other`
  - `what`, the type of event. One of:
    - `rename`
    - `modify`
    - `create`
    - `destroy`
    - `owner`
    - `other`
  - `when`, the time of the event in nanoseconds since epoch.

I'm thinking about changing them like so:

old	new
where	path_name
kind	path_type
when	effect_time
what	effect_type

I think these names make things a bit more clear in most cases.

However, I'm not sure that the field naming is important enough to break some existing programs out there (even in major version 0).

Let's let the poll decide...