@brief Method is used for obtaining a category with the specified identifier from the current location.
@param id category identifier.
@return @see Category "Category" of the current location with the specified identifier, if it exists. If category with the specified identifier doesn't exist, function returns null.
@brief Method returns location elevation graph @see ElevationGraph "ElevationGraph"
for specified tag
@param tag Graph tag in CMS
@return Elevation graph instance or null.
@return @see ElevationGraph "ElevationGraph" of the current location with the specified tag, if it exists. If elevation graph with the specified tag doesn't exist, function returns null.
@brief Method is used for obtaining a sublocation with the specified identifier from the current location.
@param id sublocation identifier.
@return The @see Sublocation "Sublocation" of the current location with the specified identifier, if it exists. If sublocation with the specified identifier doesn't exist, function returns null.