To improve the performance of the ziplist implementation, some
functions have been converted to macros to avoid unnecessary stack
movement and duplicate variable assignments.

LRANGE converted into a COW friendly command. Some refactoring, comment, and new addReply*() family function added in the process.

In the condition where the prevlen field of the next entry on insert
and delete operations needs more bytes to be properly encoded, the next
entry also needs to be updated with a new prevlen. This patch makes sure
that this effect cascades throughout the ziplist.

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

use integer types from stdint.h to be more verbose on the size in bytes of encoded elements. update list length to use 2 bytes instead of 1.