Interface for basic and full SkyNodes.

The following operations are supported. For a formal definition, please review the Service Description.

• Tables
  [BASIC] Returns an array of MetaTable
• Functions
  [BASIC] Returns MetaFunction[] with info for each function supported by the service. These are functions other than the standard ones defined in ADQL.
• Footprint
  [FULL] **NOT IMPLEMENTED** Returns a region which is the intersection of the survey and the given region.
• ExecutePlan
  [FULL] Run an ExecPlan, get back a VOData
• Columns
  [BASIC] Returns MetaColumn[] info for a given table.
• Column
  [BASIC] Returns MetaColumn[] info for a given table.
• Formats
  [BASIC] Returns a string[] of available query result formats.
• GetAvailability
  [BASIC] Returns uptime infomration about the is service
• PerformQuery
  [BASIC] Run a query, get back VOData
• QueryCost
  [FULL] Returns object count for a given criteria.
• Table
  [BASIC] Returns a MetaTable