coyote: CGMAPGRID__DEFINE

Description
This object is a wrapper for the cgMap_Grid routine in IDL. It provides a simple 
way to allow map grids on images which use a cgMAP object to set up the map 
projection space. A map coordinate space must be in effect at the time the 
Draw method of this object is used. 
Categories
Graphics, Map Projections
Author
FANNING SOFTWARE CONSULTING::
   David W. Fanning 
   1645 Sheely Drive
   Fort Collins, CO 80526 USA
   Phone: 970-221-0438
   E-mail: david@idlcoyote.com
   Coyote's Guide to IDL Programming: http://www.idlcoyote.com
History
Change History::
   Written by David W. Fanning, 7 November 2011.
   Modified AutoDrawGrid method to update, better-working method in cgMap_Grid. 28 Dec 2011. DWF.
Copyright
Copyright (c) 2011, Fanning Software Consulting, Inc.
e initialization method for the object.
Params
class: out, optional, type=structure
   Occasionally, it is useful to have an object class definition as
   a structure variable. Using this output keyword will allow that.
Keywords
success: out, optional, type=boolean
   Will be set to 1 on return, if the operation was successful. Otherwise,
   this value is set to 0.
aws the map grid by calling cgMap_Grid.
is method allows the user to get various properties of the object. In general,
e same keywords that are used for the INIT method can be used here.
is method allows the user to set various properties of the object. In general,
e same keywords that are used for the INIT method can be used here.
is is the clean-up routine for the object.
is is the class definition module. Structures used to manipulate
p projection and map datum information are also created here.