fiob library prototype.
Some test aren't passed.
Hack for all tests.
Segfaults for Roman.
fio_batch isn't used for snapshot
WAL is written as prior to.
o_direct: review fixes. Remove files committed by mistake.

Remove fiob_open_flags, use "mode" consistently.
Fix errno assignment in fiob_close().
gh-185: add slash separator for pathes that are relative from work_dir.
closes #185.
fixed GH-183 https://github.com/tarantool/tarantool/issues/183
plugins-to-lua-modules: migrate from plugins to lua modules.
Summary:
* PLUGIN_DIR -> MODULE_DIR
* MODULE_DIR prefix is /usr/lib/tarantool/VERSION
* MODULE_DIR automatically appends to both lua c/path
* removed plugin autoload facility in src/lua/init.cc
* removed admin console plugin dependencies
* moved src/box/lua/sql.lua to separate module = require('box.net.sql')
* moved src/plugin/pg = require('box.net.pg')
* moved src/plugin/mysql = require('box.net.mysql')
* default .so and .lua install is lib/tarantool/modules/{box/net/}
* debian spec and tests are updated
tarantool-sql-module: add rpm package for the module.
remove absolute prefix from MODULE_DIR
fix sql module install prefix
Drop recursive calls. Rewrite by review.
gh-183: review fixes. Use a RAII class for scoped guard.

Remove an extra block offset.
Merge branch 'fix-gh-183' into stable
module-sophia: coeio-based sophia bindings, implemented as a lua module.
move module related tests from test/box/ to test/module/.
module-sophia: debian package added.
update sophia submodule