Returning tests to their previous place. Fixing error in tarantool_connection, that prevernts reconnection. Fixing bug in cas.test

1) Lua Tarantool Server, that runs plain lua code and admin server commands (separated ';\n')
2) Python Tarantool Server, that runs old plain tests.
Also created Two types of tests, that inherit FuncTest (Cause they're FuncTest):
1) LuaTest -> Lua Tarantool Server
2) PythonTest -> Python Tarantool Server
In the future we plans to add luabench as one of Test types
Rename all cores to appropriate names of server (now it's 'lua tarantool' and 'python tarantool')
Prepare to remove lua prefixes (if you need to test wrong or nonimplemmented command you may run 'admin('cmd', simple=True)')
If you want to implement new server command - add needed regexp to admin_connection.py.
if it's fixed length command, then add it to rg1, else rg2

Move memcached to src/
Make iproto.m dependend on box/*, not vice versa.
Remove box_ prefixes from test suite names.
Initialize networking outside of box/.

This makes Box a step closer to being just a storage
layer for Tarantool.

Still some ugly deps since box/ continues to manage
local hot standby and memcached expire (todo: move it out).

macosx2: merging in (manually) previously unmerged changes (from macosx-port1), non-working tests: box/lua.test, box_big/lua.test connector_c/xlog_rpl.test

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.

Supporting 'init.lua' start up script was added to test suite.

Core:
  - salloc_destroy was removed from tarantool_free routine
Test environment:
  - new option 'valgrind_disabled' was added to suite.ini;
  - box/show test was renamed to box/admin test;
  - box/admin test was splited to admin adn admin_coredump tests.

Test enviroment:
  - old valgrind.sup file was deleted (not needed any more).
  - unused options in suite.ini files was removed.

Allow disjunctions in SELECT WHERE clause and LIMIT
clause in SELECT, to be able to cover the problem
reported in Bug#729758.

Fix a bug with prepare_gdb arguments (remove an extra
space in -e option).

Add a simple test for Bug#729758.

The following bugs were reported in the process:

Bug#729789 "Zero limit is treated the same as no limit"
Bug#730593 "Bad data if incomplete tuple"
Bug#730613 "SELECT with a disjunction on multiple keys returns
matching tuples twice"