Changes
+ Electric Furnaces have been rewritten, they now will behave similar to boilers using a virtual furnace inventory while the physical form of it is purely decorative. This should improve performance, though likely not at first, and they will now be more reliable with maintaining their inventories.
+ The Electric Furnace can now be Overdriven. When overdriven they will use a proportional amount of power and have a proportional speed increase. So overdriving it once will make it use 2x the power, but it will be 2x faster.

Fixes
+ Overdriven devices now account for their power usage properly.
+ PowerPylons now show Potential Load more accurately since they account of overdriven devices now.
+ The Electric Furnace power indicator now shows more reasons for why its not working, for example if it doesn't have output space it'll say that instead of telling the user there is no power.

Notes
+ While working on this patch I discovered an issue with Power Grids that do not use batteries. While I fix this issue I recommend always having at least one battery in your power setups. The issue is a hard one to fix right now, since ill need to add ordering to device ticking on the grid.
+ Electric Furnaces will likely convert into normal furnaces and or lose their content with this update, do to their internal changes. Sorry about this but the changes done are more then worth it as it allows the commonly requested Overdriving feature for them and improves their stability.