OS-1823 git-pbchk should not depend on mercurial

*** 15,24 ****
--- 15,25 ----
  #
  
  #
  # Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
  # Copyright 2008, 2012 Richard Lowe
+ # Copyright (c) 2013, Joyent Inc. All rights reserved.
  #
  
  import getopt
  import os
  import re
*** 26,39 ****
  import sys
  import tempfile
  
  from cStringIO import StringIO
  
- # This is necessary because, in a fit of pique, we used hg-format ignore lists
- # for NOT files.
- from mercurial import ignore
- 
  #
  # Adjust the load path based on our location and the version of python into
  # which it is being loaded.  This assumes the normal onbld directory
  # structure, where we are in bin/ and the modules are in
  # lib/python(version)?/onbld/Scm/.  If that changes so too must this.
--- 27,36 ----
*** 45,54 ****
--- 42,52 ----
  # Add the relative path to usr/src/tools to the load path, such that when run
  # from the source tree we use the modules also within the source tree.
  #
  sys.path.insert(2, os.path.join(os.path.dirname(__file__), ".."))
  
+ from onbld.Scm import Ignore
  from onbld.Checks import Comments, Copyright, CStyle, HdrChk
  from onbld.Checks import JStyle, Keywords, Mapfile
  
  
  class GitError(Exception):
*** 175,188 ****
      should be excluded from the check named by 'cmd'"""
  
      ignorefiles = filter(os.path.exists,
                           [os.path.join(root, ".git", "%s.NOT" % cmd),
                            os.path.join(root, "exception_lists", cmd)])
!     if len(ignorefiles) > 0:
!         return ignore.ignore(root, ignorefiles, sys.stderr.write)
!     else:
!         return lambda x: False
  
  
  def gen_files(root, parent, paths, exclude):
      """Return a function producing file names, relative to the current
      directory, of any file changed on this branch (limited to 'paths' if
--- 173,183 ----
      should be excluded from the check named by 'cmd'"""
  
      ignorefiles = filter(os.path.exists,
                           [os.path.join(root, ".git", "%s.NOT" % cmd),
                            os.path.join(root, "exception_lists", cmd)])
!     return Ignore.ignore(root, ignorefiles)
  
  
  def gen_files(root, parent, paths, exclude):
      """Return a function producing file names, relative to the current
      directory, of any file changed on this branch (limited to 'paths' if