This fix adds virtual method raise() to Exception classes to throw
derived type instead of base.

This patch explicitly saves Exception to a thread-local variable inside
struct cord on tnt_raise(). This variable can be used to safetly
re-throw last exception from any place (not only from catch() block).
This technique requires exception to be thrown and catched by pointers.
tnt_raise macros was rewritten and all 'catch (Exception &)' blocks were
substituted with 'catch (Exception *e)'.

This patch also adds a new feature to box.raise() function.
When called without arguments box.raise() re-throws last exception (if
any).

These changes needed to implement proper handlings of exception for FFI
calls.

Implement cord names.
Log cord names in the server log.
Try to make find_path() valgrind-clean (the bug, however,
is in glibc).

shortcut :count method

Conflicts:
	test/replication/consistent.test.lua
	test/replication/hot_standby.result
	test/replication/hot_standby.test.lua

remote:call always returns lua-table.

Important changes:
  * lua_libs are now copy from TarantoolServer (if you need, e.g.,
    to copy .lua or .xlog file when you starts server you may
    simply add it to server.lua_libs variable, and in the end
    simply delete it)
  * server now stops on random ports, for your convinience, when you
    `--start-and-exit` test-system - it shows on what port it starts
  * when you want to create a server, that is replica of some other
    server, you must do something like `replica.rpl_master = master`,
    then all will be ok. if hot_standby, then
    `hot_standby.hot_master = master`. when you stop working with it:
    `replica.rpl_master = None`..
  * new option: server.shebang is used for running scripts, no need
    to spoil server.binary now.
  * for config, init_lua and other options now there are decoreators.
    you may use relative paths now.

Other:
  * Some tests were rewritten for new TarantoolServer
  * Add `environment variables` for lua tests, possible to send it to
    server.
  * add rpl_master and hot_master for server directives in lua_tests
    (better idea, it seems, to move all `replication/` tests to python)

Some issues:
  * --valgrind:
    1. `chase_cuOff: no entry for 0x07422`... It garbages output.
    2. If you redeploy server then valgrind log is overwritten.
       Possible solutions:
         a) `valgrind_disable` this tests.
         b) Append logfile with temporary logfiles.
    3. Some memory leaks: need to be fixed.
  * --gdb: some minor code problems, all works, but tests, that
    crashes server won't work (new system of knowing that server
    is up)
  * Need of minor(!!) cleanup

Check that tuple is an msgpack array.

- Drop GE/LE iterators for HASH-index.
- min/max can receive key.
- fix all tests.

Introduce a structure to represent a thread with an event
loop in it.

Do not require a working event loop in say() or wal_opt_sync().

Allow start of tarnatool_box in #! form.

Remove script_dir.

Make all configuration options optional (primary_port
was the last one required).
Make the configuration file itself optional.

If no watcher is started for the event loop, either based on
the config file settings, or in the #! script, do not start the event loop.

Update the test runner to take the new changes into account.

Fix a bug in symbols_load() when no symbols
could be loaded when path to executable was neither
relative nor absolute (but based on PATH).

Fix a bug with ignored return value of slab_arena_create()
in tuple.cc

This patch add specialized versions of box.process for select, insert,
replace, update and delete requests. This optimization reduces the
number of Lua <-> C switches during request processing. New functions
create struct request directly without allocating temporary buffer for
entire request body.

Conflicts:
	src/box/box_lua.cc