Add npm script to pull binaries from CI, before npm publish

[vweevers]

Using prebuildify-ci download. Also, should we document this required step? @ralphtheninja

[ralphtheninja]

Using prebuildify-ci download. Also, should we document this required step? @ralphtheninja

Yeah, lets do it for transparency and if anyone is wondering about it.

[ralphtheninja]

Ps. It's also nice to have around, even if you do know it, as a check list.

[vweevers]

Ps. It's also nice to have around, even if you do know it, as a check list.

Agree, esp. because the "build flows" are now different for leveldown, rocksdb, etc