Merge branch 'maint'

Merge branch 'maint'

* maint:
  Documentation/git-clone: describe --mirror more verbosely
  do not depend on signed integer overflow
  work around buggy S_ISxxx(m) implementations
  xdiff: cast arguments for ctype functions to unsigned char
  init: plug tiny one-time memory leak
  diffcore-pickaxe.c: remove unnecessary curly braces
  t3020 (ls-files-error-unmatch): remove stray '1' from end of file
  setup: make sure git dir path is in a permanent buffer
  environment.c: remove unused variable
  git-svn: fix processing of decorated commit hashes
  git-svn: check_cherry_pick should exclude commits already in our history
  Documentation/git-svn: discourage "noMetadata"