Merge branch '1.6' into preprocessor-remove

.gitignore

.travis.yml

Doxyfile.API.in

FreeBSD/databases/tarantool/pkg-plist

cmake/module.cmake

doc/sphinx/reference/capi.rst

extra/rpm/tarantool.rpm.spec.in

src/CMakeLists.txt

src/box/alter.cc

src/box/box.cc

src/box/cluster.cc

src/box/lua/space.cc

src/box/request.cc

src/box/wal.cc

src/box/wal.h

src/cbus.c

src/cbus.h

src/coro.c

src/lib/salad/stailq.h

src/module_footer.h