Fix 10.9 Ruby.framework detection/compilation

Mac OS X Mavericks ships with Ruby.framework 2.0 which requires some
fixes to enable proper header inclusion and version defines.

src/auto/configure

@@ -7228,7 +7228,7 @@ echo "${ECHO_T}$rubyhdrdir" >&6; }
 	  RUBY_LIBS="$RUBY_LIBS -L$rubylibdir"
         elif test -d "/System/Library/Frameworks/Ruby.framework"; then
                         RUBY_LIBS="-framework Ruby"
-                        RUBY_CFLAGS=
+                        RUBY_CFLAGS="-DRUBY_VERSION=$rubyversion"
             librubyarg=
 	fi
 

src/configure.in

@@ -1734,7 +1734,7 @@ if test "$enable_rubyinterp" = "yes" -o "$enable_rubyinterp" = "dynamic"; then
             dnl On Mac OS X it is safer to just use the -framework flag
             RUBY_LIBS="-framework Ruby"
             dnl Don't include the -I flag when -framework is set
-            RUBY_CFLAGS=
+            RUBY_CFLAGS="-DRUBY_VERSION=$rubyversion"
             librubyarg=
 	fi
 

src/if_ruby.c

@@ -102,7 +102,11 @@
 # include <ruby.h>
 #endif
 #ifdef RUBY19_OR_LATER
-# include <ruby/encoding.h>
+# ifdef FEAT_GUI_MACVIM
+#  include <Ruby/ruby/encoding.h>
+# else
+#  include <ruby/encoding.h>
+# endif
 #endif
 
 #undef off_t	/* ruby defines off_t as _int64, Mingw uses long */