coyote: CGCONTAINER__DEFINE

Description
A modified IDL container with properties needed for Coyote Graphics routines.
Categories
Obejct Programming, Utility
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 the SetProperty and GetProperty method to indicate errors if
      extra keywords reach them. 3 Nov 2012. DWF.
Copyright
Copyright (c) 2011, Fanning Software Consulting, Inc.
e object initialization method.
Keywords
name: in, optional, type=string, default=selected by cgContainer.
   Use this keyword to name the object. Names are often used to select objects in 
   program code. 
uvalue: in, optional, type=any, default=none
   A storage space for storing any kind of IDL variable of importance to the user.
_ref_extra: in, optional
   Any superclass keyword can be set here.
s is the clean-up routine for the object.
s is the class definition module. Structures used to manipulate
 projection and map datum information are also created here.
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.