Using box.socket:recvfrom on udp socket causing 100% CPU
utilization instead of idle
https://bugs.launchpad.net/tarantool/+bug/1209189

secondary_indexes_enabled.

calls.

Use beginBuild(), reserve(), endBuild() to implement Index::build().
This is a pre-requisite for the refactoring of the
recovery API to make recovery of data dictionary spaces more
straightforward.

Split key part allocation and initialization in key_def_create().
This makes it possible use of the same key_def_create() when
"building" a key def for memcached space, and when building
it from the configuration file.

Make key_def.[h,cc] unaware of struct tarantool_cfg.

Instead of populating Lua box.space[] table once at
server start, update it with space data whenever it changes.
This is a pre-requisite patch for the new data dictionary,
which allows adding/dropping spaces on a running server.

Generalize session triggers to be usable for on_commit/on_rollback
events.

Remove key_def->max_fieldno as well.
Rename space_n() to space_id(), space_by_n to space_by_id().

Follow up on refactoring of struct key_def ownerhship.

Another pre-requisite patch for the new data dictionary,
transfer ownership of struct key_def from struct space
to class Index.

Once Index instance is created, it takes posession of the
key_def object passed to initialize it.

key_defs array in struct space is gone.

A pre-requisite patch for data dictionary: sotre index
ordinal number in the key_def object.
Remove struct space from index constructor.

 * Parse request type inside of request_create
 * Remove palloc from request_create
 * Replace request_execute with a fun pointer in struct request
 * Refactor box_process API to accept struct request *
 * Create requests directly in iproto.cc and box_lua.cc
 * Update memcached, recovery and other parts to use new API

Incompatible change,
https://blueprints.launchpad.net/tarantool/+spec/cardinality-arity

cardinality is how many unique elements a set contains. wrong term
for the max number of fields in a tuple

https://bugs.launchpad.net/tarantool/+bug/1200228
Remove the regression I introduced when trying to be to smart when
comparing integer numbers.

Numeric comparison is not memcmp compatible on x86, and I don't
know what I was smoking when I wrote a test which proved it wrong.

Save tuple field offsets for indexed fields in the tuple.
Merge tuple validation and initialization of field maps in the tuple.
Make formats work for an incorrect tuple.
Make tuple_field() inline.

Use formats when creating tuples.
Store format id in the tuple.

Refactor space cache code, create indexes
in space_create().

Remove init_storage option.

Move struct key_def into an own header.
Rename key_def methods to follow the coding style.
Rename field_data_type to field_type.
Instead of panicking on key_def initialization
error, throw an exception.

The allocator consists of a common slab cache, region and slab
allocators.
The patch provides unit tests.

It also modifies rlist_shift to be more in line with the
rest of rlist functions.