Add access field to Park preset

[arch0345]

A significant number of parks (~10K/1%) of parks also have an access=* tag according to Taginfo

The same can be said for Nature Reserves

[1ec5]

The Sports Center / Complex and Sports Club presets should probably have this field too. There are a lot of private tennis and swimming clubs and that sort of thing.

[tyrasd]

I've added the access_simple field "only" as an optional field, because there is a strong implication of a "default access value" (i.e. for parks adding an access tag is only required in the exceptional cases when they are not public, and sports centers/clubs can similarly assumed to be for customers/members only): In these cases it wouldn't add too much information if we asked mappers to fill in this field all the time.

For nature reserves, it's unfortunately a bit unclear what "access" specifically means for such map features (the wiki doesn't explicitly mention the usage). If it's about accessing any part of the respective areas, this can quickly lead to ambiguous situations like here or here, where I would strongly assume that accessing the main roads, paths and railways through the nature reserves is allowed, despite the access=private on the areas. If access in this case should only "affect" the areas outside of the road/path network, we'd need a more specific field (label) IMO. I have still included the tag as an optional field, to at least show the currently mapped information.