'print_log'`

Conflicts:
	src/box/lua/box_net.lua
	test/box/ipc.test
	test/box/net.box.result

 + memory leak in box.net.box (timeouted responses)
 + remote:ping() never throw exception

Conflicts:
	doc/user/target.db
	src/ipc.cc
	test/box/ipc.test

Conflicts:
	doc/user/stored-procedures.xml

Conflicts:
	src/box/CMakeLists.txt

Conflicts:
	src/lua/init.cc
	test/box/fiber.result
	test/box/fiber.test
	test/module/net_sql.mysql.result
	test/module/net_sql.mysql.test

Closes #161

Conflicts:
	.gitmodules
	CMakeLists.txt
	extra/rpm.spec.in
	src/CMakeLists.txt
	src/box/box.cc
	src/box/box.h
	src/log_io.cc
	src/recovery.cc
	src/tarantool.cc
	test/unit/CMakeLists.txt
	test/unit/test.c

Fix styler
Clarify tricky pieces of the code (at least make them clearer to yours
truly).
Fix a bug with incorrect return value from fwrite() & O_DIRECT.