script_dir option defines path to a directory which contains the init.lua file.

Make snap_io_rate_limit and io_collect_interval dynamic.
Add a test case.
Update the user guide.

Update the manual and the configuration file
to reflect the new WAL writer architecture.

This reverts commit 8dc70aac.

This patch introduces wal_mode configuration variable,
which can take either "fsync" or "fsync_delay" values.

In "fsync" mode, we open the write ahead log in O_SYNC
mode, and thus sync every write to disk.

Th fsync_delay mode is the backward-compatible mode:
in this mode, we only do fsync once every fsync_delay
seconds. If fsync_delay is 0, there is no fsync.

Otherwise, this patch is only adding auxiliary headers,
object files, etc.

paramaters use floating point representation.

lua.result was somehow missed in the last commit, add now

https://blueprints.launchpad.net/tarantool/+spec/namespace-to-space

Rename 'namespace' to 'space' everywhere:
in configuration, in implementation, in documentation.

Now that confetti supports it, use boolean for true/false
yes/no config options.
Update the manual accordingly.

Remove auto-generation of tarantool_box_cfg.cfg.
This was intended as a sample configuration
file, but it is no longer syntactically correct,
and thus can not be used.
Besides, there are now semantical rules on top
of the syntax restrictions (e.g. you can't define
memcached_expire on a replica), which also
make the auto-generated config incorrect.

Remove it to not mislead first-time users into
trying it out.

Test enviroment:
  - start/stop server routine was updated.
Tests:
  - fix double start srvers.

* valgrind suppresions update

* core signal handling sigaction -> libev
* suppresion file updated

* test-suite valgrind support

Rename hot_standby back to local_hot_standby. Let's
not break compatibility without a strong need.

Merge replication_source_ipaddr and replication_source_port
to a single variable, replication_source, to be able to
provide a list of sources in future.

Update comments in the configuration file.
Remove custom proc title for replication, use custom_proc_title of
the main process.
Renames.

Blueprint 'Make memcached protocol an alternative, not a replacement':

Blueprint was implemented. Memcached now can work
in presence of RELOAD CONFIGURATION statement, even if it
changes a replica to master or a master to replica.

'memcached' configuration file option was removed.
Instead, two new optinos were added:
- memcached_port - optional, default 0, if set, specifies
which port speaks memcached protocol.
- memcached_expire, boolean, which defines whether or not
we run expire on memcached namespace. If not set,
we simply support the protocol, but ignore TTL and never
expire the keys.

Original memcached test was ported to tarantool testing environment.
cas test was disabled, because tarantool has a non-critical bug (in
concurrent environment cas operation can return 'SERVER_ERROR' instead of
'EXISTS')

Replicator was updated:
 - bind replicator poer strategy was changed.
 - terminate child routine for spawner process during exit was added.
 - handle EPIPE error was added to client handler process.
 - remote_hot_standby was deleted.
 - local_hot_standby was renamed to hot_standby.
 - sender_send_sock function was fixed.
 - I/O event processing in replicator fibers was updated.

Fiber:
 - fiber_io_* functions now public.

Update *.cfg files to newer confetti and comments
in the templates.

Code review: reformat comments.
Add comments to fiber.h.
Use tnt_FiberCancelException solely to cancel fibers.
Fix alignment of fiber_server.
Use newer confetti.

Reverse the try/finally wrapping of some fiber functions
as unnecessary.

Implement
https://blueprints.launchpad.net/tarantool/+spec/feeder-in-core

- replicator was implemented;
- 'box_replication' tests was added top test suite;
- feeder module was removedl;
- tarantool's core file was of UTILITY and STORAGE defines;
- fiber name length was upped to 32 characters;
- .gitignore file was updated.

Explain how to configure a namespace.
Tweak some error messages on the way.