Summary: "plugin-build" command will produce dir with unpacked plugin sources in addition to tar package. This is required because for publishing to Marketplace we need to retrieve few files from the output package, like "readme.md" and "package.json" and it's better to have it already unpacked rather than pack and then unpack to get these files.
Reviewed By: passy
Differential Revision: D28409930
fbshipit-source-id: 51c8eeb848a72850a2f126eb91a563d52851ed41
b5d8f6c63d