Version 2.15 Patchlevel 6 Added Features/Bug Fixes

1. Fix a bug which caused bad PostScript command (0 0 atan) to be generated for a line segment of 0 width and height. Thanks to Edmond Mesrobian <edmond@cs.ucla.edu> for pointing out the problem.

2. Fix a bug which caused segmentation fault when Tgif*PercentPrintReduction is set to any value other than 100. Thanks to Dietrich Bartel <d.bartel@kfa-juelich.de> for pointing out the problem.

3. Fix something that looks like a typo. In xbitmap.c, atof()'s declaration was skipped for ANSI C or C++ for unknown reason. It is put back in as:

   extern double atof ARGS_DECL((const char *));

   If it causes any problem, please let me know. In general, I recommand using the -D_NO_EXTERN and -D_NO_PROTO compile options and not using ANSI because, as far as I can see, multi-platform ANSI standard does not works, yet. It seems that it always need some tweeking.