[btcsuite/btcd] 7cc630: docs: Change error in heading

[Steven Roose]

  Branch: refs/heads/master
  Home:   https://github.com/btcsuite/btcd
  Commit: 7cc630b3358b7dcd19d8e1d2d9f57e4959ee7c0d
      
https://github.com/btcsuite/btcd/commit/7cc630b3358b7dcd19d8e1d2d9f57e4959ee7c0d
  Author: Steven Roose <stevenro...@gmail.com>
  Date:   2016-11-12 (Sat, 12 Nov 2016)

  Changed paths:
    M docs/code_contribution_guidelines.md

  Log Message:
  -----------
  docs: Change error in heading