Dev-freeze fixes and tweaks

* Adds variable power setting for heaters and freezers
* Makes APC cell type an actual type, APCs in areas with heavy machinery come with a high-power cell by default.
* Fixes old APC power switching bug
* Reduces SM damage rate cap
* Fixes some engine bits that got copied into space accidentally.
* Increases max SMES input/output to 250 kW
Forgot to update this to be between 0 to 100.