Rock crusher can receive recipes via IMC (as requested on #332)

Not sure if it's up to your standards but I decided t give it a try :)

I made this helper method that automatically encodes all the data into a NBT tag and sends it. Thought it would be useful in case you want to include it somewhere to help people figure out how to use the message properly.

```JAVA
public void addRockCrusherRecipe(ItemStack input, boolean matchMeta, boolean matchNBT, Map<ItemStack, Float> outputs) {
	NBTTagCompound nbt = new NBTTagCompound();

	NBTTagCompound inputNBT = new NBTTagCompound();
	input.writeToNBT(inputNBT);
	nbt.setTag("input", inputNBT);

	nbt.setBoolean("matchMeta", matchMeta);
	nbt.setBoolean("matchNBT", matchNBT);

	int outCount = 0;
	for (Entry<ItemStack, Float> output : outputs.entrySet()) {
		NBTTagCompound outputNBT = new NBTTagCompound();
		output.getKey().writeToNBT(outputNBT);
		outputNBT.setFloat("chance", output.getValue());
		nbt.setTag("output" + outCount++, outputNBT);
	}

	FMLInterModComms.sendMessage("Railcraft", "rock-crusher", nbt);
}
```