growl: Add OS X user notifications as fallback to Growl notifications

This adds native OS X user notifications as fallback, if Growl is
currently not running. Those native notifications are only available
on 10.8+, therefore some preprocessor conditionals prevent that this
breaks 10.7 compilation.
There is no explicit check if the class is available as it should be
on all 10.8 systems.
Signed-off-by: Felix Paul Kühne <fkuehne@videolan.org>

modules/notify/Makefile.am

@@ -2,7 +2,7 @@ notifydir = $(pluginsdir)/notify
 
 libgrowl_plugin_la_SOURCES = notify/growl.m
 libgrowl_plugin_la_OBJCFLAGS = $(AM_OBJCFLAGS) $(OBJCFLAGS_growl)
-libgrowl_plugin_la_LDFLAGS = $(AM_LDFLAGS) -rpath '$(notifydir)'
+libgrowl_plugin_la_LDFLAGS = $(AM_LDFLAGS) -rpath '$(notifydir)' -Wl,-framework,AppKit
 libgrowl_plugin_la_LIBADD = $(LIBS_growl)
 libgrowl_plugin_la_LIBTOOLFLAGS = --tag=CC