CHANGES:
11/30/12 dpg Updated play to version of Yorick. Reworked the config and build.
05/28/06 mdh Fixed the DrwText routine in gist/ps.c to deal correctly with
strings of zero length. This bug caused crashes when plt("") was called and
a hardcopy was made. The event loop was changed for Windows, Cygwin, and
Mac OS X; the event loop now works the same on Windows, Cygwin, Mac OS X, and
Unix/X11.  Some smaller fixes (memory leaks) on Mac OS X.
11/11/05 dpg/mdh Fix a memory leak in setkw_string. Replaced tabs by spaces
in gistCmodule.c.
07/30/05 dpg/mdh Replace int's with long's where needed in src/gistCmodule.c
for 64-bits linux. Modify setup.py to set the library search path to
/usr/lib64 for 64-bits linux. Change the order in which different options
are tried in the find_poll function in setup.py for gist to compile correctly
on Mac OS X 10.4. The new setup.py was also tried on Windows, Linux, Cygwin,
and older versions of Mac OS X; no problems were found.
11/16/04 llc Fix GxPointClick; replace ifdef on this w/ MOUSE_CLICK.
mouse function was not working because of this.
11/09/04 mdh The Py_InitModule4 needs to be called even if the module
has already been initialized.  Move the initialized test. 
11/08/04 mdh Added a couple of changes for Mac OSX.
11/04/04 dpg Changed TRY macro to return a MemoryError only if an 
exception has not already been raised (in which case, it
returns NULL). Also, fixed casting warning in contour's TRY 
with PyTuple_GetSlice, changing 0 to (PyOject*) NULL.
11/03/04 dpg Discovered that beginning with Numeric 23.4, which has
stricter type checking (problems converting longs to ints),
PyArray_INT had to be changed to PyArray_LONG. (else there
were problems in plc, ...).
04/22/03 llc Fix bug in PLF.
04/08/03 llc Remove include of limits.h and unused defines;
Replace DISPLAY_ENGINE with GpFXEngine, DISPLAY_MOUSE with
GxPointClick, and DISPLAY_ZOOM_FACTOR with gxZoomFactor, and
remove use NO_XLIB, and NO_MOUSE. 
04/07/03 mdh Implement justify option for plt (align).
Add functions as those in style.i in yorick to allow
allow users to change style properties interactively:
get_text_attributes, get_legend, get_line_attributes,
get_axis_style, get_tick_style, get_system, 
get_systems_list, get_style, ... similarly for set*.
03/25/03 dpg Provide a way to change CGM file size via pldefault.
03/12/03 llc Remove version and help comments; add to gist.py.
02/25/03 llc Fix mouse command so data is returned.
02/20/03 llc Correct mouse return; see MouseCallBack.
02/13/03 llc Disable initial pygist printout upon import (except 
when DEBUG flag is on).
02/13/03 dpg Add plremove implementation. 
Correct bug in pli (iMax anad JMax were reversed).
01/17/03 llc Remove remaining warnings with gcc 2.96 by:
- Reduce to one dummy for file
- Remove dumpFreeList, Add1 cumsum, equal, greater, 
greater_equal, less, logical_and, not_equal, 
WeightedHist if not INCLUDE_EXTRA_GISTCODE.
01/13/03 mdh Add back on omitted bug fix for Windows (wait_for_expose).
12/27/02 mdh Windows/Cygwin adjustments (e.g. pyg_on_idle calls for
Windows); fix formats for pointers.
12/04/02 dhm more fixes to get pygist working under windows, _tkinter
Macros for proper printing to stdout and stderr.
Add pyg_unhook, pyg_idler, pyg_pending, and pyg_register.
11/26/02 llc Add documentation on plg markers.
11/25/02 dhm Rework of play resulted in change to PyOS_InputHook and
other improvements (multi-line strings).
11/24/02 dhm fix event/exception handling interface
11/19/02 llc Use gist interface provided by Dave Munro for PyOS_InputHook.
Remove old solutions now that play/unix has changed.
11/15/02 mhd Add u_enterloop for third approach to interfacing Python
to gist.  Save the last approach as USE_U_WAITER.
11/13/02 llc Add back option to switch between two interfaces to Python.
(using define USE_RL_GETC)
11/11/02 llc Add Numeric to arrayobject.h include, so it is found
automatically when the Python include directory is searched.
(suggestion from MDH)
11/08/02 llc Use the PyFPE_START_PROTECT and PyFPE_END_PROTECT 
macros defined in the standard Python include pyfpe.h.
Add a dummy argument to PyFPE_END_PROTECT.
11/07/02 llc Clean up some compiler warnings:
Get rid of SETERR macro; used just once.
Correct format for writes of longs in debug_array, PrintColor.
Add explict casts to ERRSS where required.
Remove unused variables.
Cast u_waiter properly, and note possible issue.
11/01/02 mdh Replace rl_getc_function with PyOS_InputHook.
09/04/02 llc Deep copy string returned from PyString_AsString
in setkw_string.
12/17/01 llc Add documentation lines to slice2.
12/06/01 llc Remove fix for E_TEXT type entries in legend; these
are legitimate.
12/03/01 llc Discovered that new setting of zc in plf causes 
unaligned accesses on DEC Alpha; go back to earlier
form setting temporary zc1.
With this change, test suite runs to completion.
11/29/01 llc Set rgb for triples.
bytscl: Change len to long.
11/16/01 llc Update to 1.5's legend handling. 
11/12/01 llc Unpack color triples.
Colors changed from int to unsigned long (1.4 to 1.5).
Check for negative colors.
11/08/01 dhm Turn on idle function to do graphics tasks.
11/05/01 llc Move all of the function documentation from gist.help
to doc strings for each PyObject, so it can be accessed 
with pydoc.
11/03/01 llc Started from version with changes from Dave Munro:
turn on rl_getc_function, and add readline.h include. 
Must use with version of python built with readline.

Modified in December, 1997 to coexist with the readline library used
in Python's interpreter. William Magro, Cornell Theory Center.
