Update vendor deps

vendor/github.com/blevesearch/segment/maketesttables.go

vendor/github.com/syndtr/goleveldb/leveldb/db.go

vendor/github.com/syndtr/goleveldb/leveldb/db_write.go

vendor/github.com/syndtr/goleveldb/leveldb/iterator/iter.go

vendor/github.com/syndtr/goleveldb/leveldb/memdb/memdb.go

vendor/github.com/syndtr/goleveldb/leveldb/util/util.go

vendor/golang.org/x/net/context/context.go

vendor/golang.org/x/net/html/atom/gen.go

vendor/golang.org/x/net/html/atom/table.go

vendor/golang.org/x/net/html/const.go

vendor/golang.org/x/net/html/doc.go

vendor/golang.org/x/sys/unix/mkpost.go

vendor/golang.org/x/sys/unix/types_darwin.go

vendor/golang.org/x/sys/unix/types_dragonfly.go

vendor/golang.org/x/sys/unix/types_freebsd.go

vendor/golang.org/x/sys/unix/types_netbsd.go

vendor/golang.org/x/sys/unix/types_openbsd.go

vendor/golang.org/x/sys/unix/types_solaris.go

vendor/golang.org/x/text/encoding/charmap/maketables.go

vendor/golang.org/x/text/encoding/htmlindex/gen.go