- Abort configure if Xft was requested explicitly, but not found.
- Set config.h HAVE_* variables only if both library and header found.
- Replace deprecated configure macros with recommended ones.
- Improve indenting (clarify macro arguments).
- Remove all autoconf warnings (see autoconf --warnings=all).
- Normalize indenting with tabs+spaces.
git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3-porting@11999 ea41ed52-d2ee-0310-a9c1-e6b18d33e121