Merge branch 'nd/wildmatch' into next

Merge branch 'nd/wildmatch' into next

Allows pathname patterns in .gitignore and .gitattributes files
with double-asterisks "foo/**/bar" to match any number of directory
hierarchies.

I suspect that this needs to be plugged to pathspec matching code;
otherwise "git log -- 'Docum*/**/*.txt'" would not show the log for
commits that touch Documentation/git.txt, which would be confusing
to the users.

* nd/wildmatch:
  Support "**" wildcard in .gitignore and .gitattributes
  wildmatch: make /**/ match zero or more directories
  wildmatch: adjust "**" behavior
  wildmatch: fix case-insensitive matching
  wildmatch: remove static variable force_lower_case
  wildmatch: make wildmatch's return value compatible with fnmatch
  t3070: disable unreliable fnmatch tests
  Integrate wildmatch to git
  wildmatch: follow Git's coding convention
  wildmatch: remove unnecessary functions
  Import wildmatch from rsync
  ctype: support iscntrl, ispunct, isxdigit and isprint
  ctype: make sane_ctype[] const array

Conflicts:
	Makefile