Few fixes, few bugs

- Removed portal generation code from blockof
- Attempted fix with blast furnace converting the world into itself.
- Updated portal
- Fixed portal comparator
- Added portal activation sequence (pretty cool if I do say-so myself)
- Fixed gravigun interaction
------ WARNING! -------
** There is a smallish bug with the energynet tiles at this point, where
they cause the tile updater to go a bit haywire and crash without giving
an actual explanation of what caused the crash. There will be a fix,
eventually...