Merge branch 'master' of github.com:tarantool/tarantool

doc/user/configuration-reference.xml

doc/user/databases.xml

doc/user/lua-and-packages.xml

doc/user/stored-procedures.xml

doc/user/triggers.xml

doc/user/user.xml

extra/tarantool.rb

src/box/alter.cc

src/box/key_def.h

src/box/lua/schema.lua

src/box/user.cc

src/box/user.h

src/box/vclock.h

src/errcode.h

src/lua/bsdsocket.lua

test/box/bsdsocket.result

test/box/bsdsocket.test.lua

test/box/misc.result

test/box/role.result

test/box/role.test.lua