See issue #3114.

bitops/bitfield: fix length, overflow condition and *sign

We want to report the original command in the stats, for example GEOADD,
even when what is actually executed is the ZADD implementation.

The new bitfield command is an extension to the Redis bit operations,
where not just single bit operations are performed, but the array of
bits composing a string, can be addressed at random, not aligned
offsets, with any width unsigned and signed integers like u8, s5, u10
(up to 64 bit signed integers and 63 bit unsigned integers).

The BITFIELD command supports subcommands that can SET, GET, or INCRBY
those arbitrary bit counters, with multiple overflow semantics.

Trivial and credits:

A similar command was imagined a few times in the past, but for
some reason looked a bit far fetched or not well specified.
Finally the command was proposed again in a clear form by
Yoav Steinberg from Redis Labs, that proposed a set of commands on
arbitrary sized integers stored at bit offsets.

Starting from this proposal I wrote an initial specification of a single
command with sub-commands similar to what Yoav envisioned, using short
names for types definitions, and adding control on the overflow.

This commit is the resulting implementation.

Examples:

    BITFIELD mykey OVERFLOW wrap INCRBY i2 10 -1 GET i2 10

Fixes double conversions in GEO

Send a long double or double as a bulk reply, in a human friendly
format.

Related to issue #3019.

Now elements added to lists are incremental numbers in order to
understand, when inconsistencies are found, what is the order in which
the elements were added. Also the error now provides both the expected
and found value.

Close #3086.

cmsgpack: pass correct osize values to lua allocator

Adds keyspace notifications for LREM

We need to be able to correctly parse the node address in the case of
IPv6 addresses.

CLUSTER SLOTS now includes IDs in the nodes description associated with
a given slot range. Certain client libraries implementations need a way
to reference a node in an unique way, so they were relying on CLUSTER
NODES, that is not a stable API and may change frequently depending on
Redis Cluster future requirements.