Include file cleanups..
Add <limits.h> to the include files handled by "cache.h", and remove
extraneous #include directives from various .c files. The rule is that
"cache.h" gets all the basic stuff, so that we'll have as few system
dependencies as possible.
diff --git a/cache.h b/cache.h
index 28e3dbd..d38d9a8 100644
--- a/cache.h
+++ b/cache.h
@@ -10,6 +10,7 @@
#include <stdarg.h>
#include <string.h>
#include <errno.h>
+#include <limits.h>
#include <sys/mman.h>
#include <sys/param.h>
#include <netinet/in.h>
