builds being excluded on npm

[hudsonhyunlim]

Is there any reason to exclude builds directory from npm?

https://github.com/moment/moment-timezone/blob/develop/.npmignore#L12

There are times when pre-built packages would be easier to load in unit test environments like karma, and I don't see any drawbacks from including this in npm packages.

[swissmanu]

+1

[timrwood]

Fixed with #237