Mineflayer

* fix digging leaves not calling callback.

* add enchantment table support. See `examples/chest.js` for an example.
* rename `bot.tell` to `bot.whisper` to be consistent with 'whisper' event.
(thanks Darthfett)

* update vec3 to 0.1.3
* add "whisper" chat event

This release is feature-complete with the old
[C++/Qt based version of mineflayer](https://github.com/andrewrk/mineflayer/blob/cpp-qt-end).

* add `bot.activateItem()`
* add `bot.deactivateItem()`
* add `bot.useOn(targetEntity)`

* add dispenser support
- add `mineflayer.Dispenser`
- add `bot.openDispenser(dispenserBlock)`

* add furnace support
- add `mineflayer.Furnace`
- add `bot.openFurnace(furnaceBlock)`
* `mineflayer.Chest`: "update" event renamed to "updateSlot"
* `bot.equip(itemType, destination, [callback])` changed to
`bot.equip(item, destination, [callback])`. Use `bot.inventory.items()`
to get a list of what items you can choose from to equip.
* fix `bot.openChest` not working for ender chests
* fix incorrectly scaled fuel percentage
* upgrade to minecraft-protocol 0.7.0
- `mineflayer.createBot` no longer takes a `email` argument.
- The `username` and `password` arguments are used to authenticate with the
official minecraft servers and determine the case-correct username. If
you have migrated your user account to a mojang login, `username` looks
like an email address.
- If you leave out the `password` argument, `username` is used to connect
directly to the server. In this case you will get kicked if the server is
in online mode.