Merge branch 'nd/config-split'

Merge branch 'nd/config-split'

Split the overly large Documentation/config.txt file into million
little pieces.  This potentially allows each individual piece
included into the manual page of the command it affects more easily.

* nd/config-split: (81 commits)
  config.txt: remove config/dummy.txt
  config.txt: move worktree.* to a separate file
  config.txt: move web.* to a separate file
  config.txt: move versionsort.* to a separate file
  config.txt: move user.* to a separate file
  config.txt: move url.* to a separate file
  config.txt: move uploadpack.* to a separate file
  config.txt: move uploadarchive.* to a separate file
  config.txt: move transfer.* to a separate file
  config.txt: move tag.* to a separate file
  config.txt: move submodule.* to a separate file
  config.txt: move stash.* to a separate file
  config.txt: move status.* to a separate file
  config.txt: move splitIndex.* to a separate file
  config.txt: move showBranch.* to a separate file
  config.txt: move sequencer.* to a separate file
  config.txt: move sendemail-config.txt to config/
  config.txt: move reset.* to a separate file
  config.txt: move rerere.* to a separate file
  config.txt: move repack.* to a separate file
  ...