Eliminate duplicate npm registrations

[shanewholloway]

Node-msgpack is registered three separate times by Peter Griess

1. correctly as msgpack — lists versions (0.1.2, 0.1.3)
2. incorrectly as msgpack-0.4 — semantic versioning should be handled within registration using version metadata. Version (0.1.4)
3. unnecessarily as msgpack2 — lists versions (0.1.4, 0.1.5, 0.1.6, 0.1.7). Name change not reflected in the metadata minor version numbers, leading to confusion on why the name changed.

Proposed solution: re-publish newest versions in msgpack2 to msgpack, and remove or migrate msgpack2 and msgpack-0.4 in favor of msgpack key.