#14 Fix underlink

[Tupone Alfredo]

See:
http://blog.flameeyes.eu/2010/11/26/it-s-not-all-gold-that-shines-why-underlinking-is-a-bad-thing
and
https://bugs.gentoo.org/show_bug.cgi?id=367485

The inlined patch should fix underlink of one of the demo:

--- demo/Makefile.am.old 2011-05-20 11:13:18.822445466 +0200
+++ demo/Makefile.am 2011-05-20 11:13:28.271042994 +0200
@@ -17,7 +17,7 @@
$(NULL)
c_demo_CFLAGS = $(FT2_CFLAGS) $(GL_CFLAGS)
c_demo_LDFLAGS = $(FT2_LIBS) $(GLUT_LIBS)
-c_demo_LDADD = ../src/libftgl.la
+c_demo_LDADD = ../src/libftgl.la -lm

FTGLDemo_SOURCES = \ FTGLDemo.cpp \