Conflicts:
	mod/box/box.lua
	test/box/lua.result
	test/box/lua.test

tarantool_lua_dofile function was rewritten.

Fix brokken static compilation of the client (we'll have
to find another solution for Darwin).

Review changes:
  * tarantool_lua_load_startup was renamed to tarantool_lua_load_init_script;
  * TARANTOOL_LUA_STARTUP was renamed to TARANTOOL_LUA_INIT_SCRIPT;
  * init.lua int the test suite is optional now;
  * Additional comments was added.

Fix bug https://bugs.launchpad.net/tarantool/+bug/988701
"Build with '-DENABLE_CLIENT=true' was broken'

Until
https://bugs.launchpad.net/tarantool/+bug/962848
"Compilation with extrnal LuaJIT broke with addition of FFI"
is fixed, don't try to compile with external LuaJIT.

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