Fix for latest HB changes
Fix automake warning

warning: 'INCLUDES' is the old name for 'AM_CPPFLAGS' (or '*_CPPFLAGS')
Modernize automake invocation
Use C99
Common GNOME configure stuff
Cosmetics
Attempt to properly set buffer script

Now using Pango script iterator to do proper script analysis. Not quite
right yet as we need to do proper BiDi as well.
Use pango_itemize() for script & bidi itemisation
Cosmetic