added madvise, smaller mmap()ed windows and local-buffering (step 1 and 2 of the optimizations)
added madvise, smaller mmap()ed windows and local-buffering
(step 1 and 2 of the optimizations)


git-svn-id: 77a2ea9ad361e718a11071bafecd9426888b997a@796 152afb58-edef-0310-8abb-c4023f1b3aa9

ctdk/lighttpd-1.4.x,ctdk/lighttpd-1.4.x,ctdk/lighttpd-1.4.x,ctdk/lighttpd-1.4.x