Sentinel uses execve to run scripts, so it needs to use FD_CLOEXEC
on all file descriptors, so that they're not accessible by the script it runs.
This commit includes a change to the sentinel tests, which verifies no
FDs are left opened when the script is executed.
networking related stuff moved into networking.c
moved more code
more work on layout of source code
SDS instantaneuos memory saving. By Pieter and Salvatore at VMware ;)
cleanly compiling again after the first split, now splitting it in more C files
moving more things around... work in progress
split replication code
splitting more
Sets split
Hash split
replication split
even more splitting
more splitting
minor change
