Merge branch 'master' (early part) into pd/bash-4-completion

Merge branch 'master' (early part) into pd/bash-4-completion

* 'master' (early part): (529 commits)
  completion: fix zsh check under bash with 'set -u'
  Fix copy-pasted comments related to tree diff handling.
  Git 1.7.3.2
  {cvs,svn}import: use the new 'git read-tree --empty'
  t/t9001-send-email.sh: fix stderr redirection in 'Invalid In-Reply-To'
  Clarify and extend the "git diff" format documentation
  git-show-ref.txt: clarify the pattern matching
  documentation: git-config minor cleanups
  Update test script annotate-tests.sh to handle missing/extra authors
  Better advice on using topic branches for kernel development
  Documentation: update implicit "--no-index" behavior in "git diff"
  Documentation: expand 'git diff' SEE ALSO section
  Documentation: diff can compare blobs
  Documentation: gitrevisions is in section 7
  fast-import: Allow filemodify to set the root
  shell portability: no "export VAR=VAL"
  CodingGuidelines: reword parameter expansion section
  Documentation: update-index: -z applies also to --index-info
  gitweb: Improve behavior for actionless path_info gitweb URLs
  gitweb: Fix bug in evaluate_path_info
  ...

Conflicts:
	GIT-VERSION-GEN
	RelNotes
	contrib/completion/git-completion.bash