Merge remote-tracking branch 'origin/1.9' into 1.10

src/box/lua/schema.lua

src/box/lua/session.c

src/box/memtx_bitset.c

src/box/memtx_bitset.h

src/lib/bitset/bitset.c

src/lib/bitset/bitset.h

src/lib/bitset/expr.c

src/lib/bitset/expr.h

src/lib/bitset/index.c

src/lib/bitset/index.h

src/lib/bitset/iterator.c

src/lib/bitset/iterator.h

src/lib/bitset/page.c

src/lib/bitset/page.h

test/box-tap/cfg.test.lua

test/box/access.result

test/box/access.test.lua

test/unit/bitset_basic.c

test/unit/bitset_index.c

test/unit/bitset_iterator.c