Minecart with TNT

The Minecart with TNT is a type of minecart that acts as a moving TNT block.

Behavior
A minecart with TNT can only be placed on a rail. Once it is pushed it will start to go along the rail like a rideable minecart.

It will detonate on these conditions:
 * It moves over a powered Activator Rail (after 4 second delay like the TNT block).
 * It derails and falls more than three blocks.
 * It's destroyed while in motion.
 * It's destroyed by fire, lava or an explosion.
 * It turns on a curved track with a solid block or entity located beside the track (in the previous movement direction).

Upon detonation, it will act as normal TNT, exploding and damaging nearby scenery, players, and mobs. A useful fact about these TNT minecarts is that upon detonation after activating on Activator Rail, it will not destroy its rails and the blocks the rail is on. Note: Even though the rails and supports will be left unharmed, you will still take damage from the explosion, so make sure to be a reasonable distance from the cart. Minecarts with TNT can be used as a less complicated alternative to the conventional TNT cannon, requiring only one block of TNT.

Trivia

 * Unlike what can be seen when one Minecart with TNT detonates, stacking multiple carts into each other can destroy the rails that they were on.
 * It is possible to create an enormous crater using several Minecart with TNT's and having them all detonate at the same time. This will kill players wearing full-diamond armor and the resulting fall to the ground will deal well beyond what any armored player can resist in damage (hundreds of hearts worth). A direct hit from three stacked Minecarts can reduce a fully diamond armored player to half a heart.
 * TNT Minecarts will not destroy rails or their supports upon detonation. It will, however, destroy blocks around and below the supports, so if they are made out of sand, the track will fall apart.
 * They cannot be set off by Flint and Steel or fire. However, if a launched Fire Charge hits a Minecart with TNT, it will explode instantly, making it good for insta-landmines. Shooting them with a bow with the flame enchantment will set the minecart on fire but nothing will happen. Even when removing all the blocks underneath it the minecart will just float in the air and keep burning. Logging out and logging back in will fix this problem.
 * As with any minecart, placing 3 or more together and allowing them to exit a rail system will cause them to glide orthogonally or diagonally at an orthogonal movement speed similar to the player's walking speed. This means that, especially on flat-lands, TNT carts can be used as long-range weapons. Note that any wall at all or dip of over 1 block depth will cause the self-propelling TNT-carts to explode all at once, creating a large crater and killing players. This can also occur on contact with players, making TNT-carts the only weapon capable of being launched and exploding on contact with players instead of terrain.
 * If the minecart derails into fire, it will immediately explode while the minecart will be destroyed and will drop a minecart and strangely, with a TNT block, despite the explosion. (Tested in Creative mode.) Also, noted that the player does not take any damage from the explosion in Survival, making it easy to mine surface blocks, or clear out landscapes for building. Tested and works from 1.5.1 on.
 * If you stack multiple minecarts onto each other and then drop lava on it,the first minecart will explode and the others fall a bit down instead of all minecarts exploding at the same moment. After this the lava will contact again and the second one will explode, etc. etc. etc.
 * If you sit in a minecart with TNT, it will act like an x-ray machine