WIP: Changing the balance designs of mechanic.
Adjusted material generation values. Plastic is now fixed at ~10% of total cost.

Moved some procs relating to designs from rdmachines to designs.dm
Added flatpack instructions.
Added plastic sheets to map.
Added plastic, fixed merge conflicts.
Fix merge conflicts.
Changelog.
Added flatpacks to changelog.
Merge pull request #1900 from ComicIronic/MechanicPort

[WIP] Changing the balance designs of mechanic.