Convert master part list to json

[royfalk]

Provide a master_part_list.json file for the engine to use. Also provide a script - migrate_parts. Once the script is used, you need to manually delete the headers and add 0 in empty price fields.

See also https://github.com/vegastrike/Vega-Strike-Engine-Source/pull/711 Code Changes:

• [x] Have the PR Validation Tests been run? See https://github.com/vegastrike/Vega-Strike-Engine-Source/wiki/Pull-Request-Validation

Issues:

• None identified