Implementation of an XML Schema describing a Cone Search Service.
Based on "Simple Cone Search: a First Guide for Data Curators",
http://www.us-vo.org/metadata/conesearch/.
Diff:
The capabilities of a Cone Search implementation. It includes
the listing of the columns that appear in image query
output VOTable and Cone Search-specific metadata.
The largest number of records that the service will return.
The largest search radius, in degrees, that will be
accepted by the service without returning an error condition.
Use 180.0 if there is no restriction.
True if the service supports the VERB keyword; false, otherwise.