This patch merges row_header and wal_row structures into new
log_row structures.

Change box.error to push error codes without error flags.

Update the protoco spec in doc/box-protocol.txt.
Update box.net.box with a bunch of hacks.
Update the python driver.

Remove support for flags variable (BOX_RETURN_TUPLE).
It was not tested anywhere! (-> kill)

Implemeng Lua msgpack.next() to support streamed processing.
Add tests.

Fix a bug with messed up aliases of msgpack.dumps() pointing
to encode() and loads() pointing to decode() (should be vice versa).

Introduce constants for ids. Update tests.

Conflicts:
	src/box/tree_index.cc
	src/box/tree_index.h
	test/big/tarantool.cfg
	test/box/errinj.result

fixes, follows from discussion https://github.com/tarantool/tarantool/issues/79#issuecomment-29309533

Conflicts:
	extra/static.py

    1. Unified blurb for every site page
    2. remove tnt-html.xsl.cmake tnt-html-chunk.xsl.cmake in favor of
    --stringparam and -param flags of xsltproc and saxon
    3. Create flags for input/output in static.py script for OOS build