some patches

cygwin's makefile may be usable for other platforms as well - there were complains that the whole thing fails to link, and this makefile was tested with clang 3.4 (compiled from source under cygwin). that, stdio.h, and some cc-mode fixes (you can't just ignore java, or duplicate the cc-mode hook from original ac, because then when the user tries to fix that by hooking up to not-common mode, magic happens. magical clusterfuck that is.). worth merging i guess.