place/add - Creates a new place.

Method parameters:
latitude - The latitude of the place.
longitude - The longitude of the place.
altitude - The altitude of the place.
name - The name of the place.
description - The description of the place.
tags - A space-separated list of tags.

Returns a JSON document of the following format:
<number> - The ID of the newly created place.

Expected errors:
TOO_MANY_TAGS - More than 5 tags given.