[conformal/btcd] eee338: Update mining-related RPC handlers for new code.

[Dave Collins]

  Branch: refs/heads/master
  Home:   https://github.com/conformal/btcd
  Commit: eee338cbe32b09e9ee666e0f5b40c607da3b31ec
      
https://github.com/conformal/btcd/commit/eee338cbe32b09e9ee666e0f5b40c607da3b31ec
  Author: Dave Collins <da...@conformal.com>
  Date:   2014-06-12 (Thu, 12 Jun 2014)

  Changed paths:
    M rpcserver.go

  Log Message:
  -----------
  Update mining-related RPC handlers for new code.

Now that btcd support CPU mining, update the getgenerate, setgenerate,
gethashespersec, and getmininginfo RPC handlers to return the appropriate
information.

Also, remove the various extra help addenda about btcd not supporting
mining since it is no longer true.