- fixed missing stdlib.h and string.h includes everywhere
- removed a couple of unneeded stdlib.h and stdio.h includes

diff --git a/server/file.c b/server/file.c
index df7af68..3bb6168 100644
--- a/server/file.c
+++ b/server/file.c
@@ -7,6 +7,7 @@
 #include <assert.h>
 #include <fcntl.h>
 #include <stdio.h>
+#include <string.h>
 #include <stdlib.h>
 #include <errno.h>
 #include <sys/errno.h>