MP tables as release asset.

[dustinswales]

Problem: Currently the MP tables for TEMPO, and UGWPv1 (?), are stored on an external server and downloaded as part of our CI testing workflow. This requires us coordinate with someone with access to the external server.

Solution: Store MP tables as release assets (in GitHub).

[clark-evans]

Addressed with recent releases, and integral to #218. Will set #218 to close this issue when merged.