[Freetype] autoconf piece for getting freetype version

[Lars Clausen]

I now have a nicer piece of autoconf for checking the freetype version:

    AC_MSG_CHECKING([if FreeType version is 2.0.9 or higher])
    old_CPPFLAGS="$CPPFLAGS"
    CPPFLAGS=`freetype-config --cflags`
    AC_TRY_CPP([#include <freetype/freetype.h>
#if (FREETYPE_MAJOR*1000+FREETYPE_MINOR)*1000+FREETYPE_PATCH < 2000009
#error Freetype version too low.
#endif
],
        [AC_MSG_RESULT(yes)
         FREETYPE_LIBS=`freetype-config --libs`
         AC_SUBST(FREETYPE_LIBS)
         AC_DEFINE(HAVE_FREETYPE,1,[Define if you have the FreeType2 library])
         CPPFLAGS="$old_CPPFLAGS"]
    ,
        [AC_MSG_ERROR([Need FreeType library version 2.0.9 or higher])])

It should be nicely encapsulated in its own macro, but I haven't gotten
that far yet.  And I'm dismayed by the need to save the CPPFLAGS, but it
works. 

-Lars

-- 
Lars Clausen (http://shasta.cs.uiuc.edu/~lrclause)| Hårdgrim of Numenor
"I do not agree with a word that you say, but I   |----------------------------
will defend to the death your right to say it."   | Where are we going, and
    --Evelyn Beatrice Hall paraphrasing Voltaire  | what's with the handbasket?