[conformal/btcutil] 4d8920: Fix up for recent btcec changes.

[Owain G. Ainsworth]

  Branch: refs/heads/master
  Home:   https://github.com/conformal/btcutil
  Commit: 4d8920c4dd6d8546bd8fac72d070b3f48d0e41bd
      
https://github.com/conformal/btcutil/commit/4d8920c4dd6d8546bd8fac72d070b3f48d0e41bd
  Author: Owain G. Ainsworth <o...@conformal.com>
  Date:   2014-04-09 (Wed, 09 Apr 2014)

  Changed paths:
    M address.go

  Log Message:
  -----------
  Fix up for recent btcec changes.