1. Fixed electric heat medium's TC calculation not working properly.

1. BigHeater can be built using diamond.
2. Added Electric Heat Medium for controlled heat conduction.

1. Fixed conduit heater running even when pipes/vents are empty.

1. Fixed Chinese translation encoding problem.
2. Fixed conduit heater power cost.
3. slightly reduced conduction vent's TC multiplier.

1. Fixed Conduction Vent not unlocked by correct tech.