Update to use 'generate' RPC

[davecgh]

Work is currently underway to implement a new 'generate' RPC which can be used to deterministically generate a specified number of blocks (btcsuite/btcd#362).

Once that is done, btcsim should be updated to use it.

[davecgh]

The generate RPC has been merged to btcd, so this can now be completed.

[tuxcanfly]

Thanks, I've been working on refactoring out some obsolete setup steps now that we don't need a peer node, async setgenerate calls and chans for waiting for blocks.

@aakselrod Can you check and try out #93? I'm seeing a few panics and some edge cases around CSV which I'm currently working on, but let me know how you feel about this approach. Thanks.

[aakselrod]

@tuxcanfly, I'm taking a look.

@davecgh, we will need btcsuite/btcrpcclient#48 merged as well for this to be completed. Please review if you have a chance.

[davecgh]

Done