"--abbrev[=<n>]" option to control the minimum
   number of hexdigits shown for commit object names.

 * "git blame" learned "--line-porcelain" that is less efficient but is
   easier to parse.

 * Aborting "git commit --interactive" discards updates to the index
   made during the interactive session.

 * "git commit" learned a "--patch" option to directly jump to the
   per-hunk selection UI of the interactive mode.

 * "git diff" and its family of commands learned --dirstat=0 to show
   directories that contribute less than 0.1% of changes.

 * "git diff" and its family of commands learned --dirstat=lines mode to
   assess damage to the directory based on number of lines in the patch
   output, not based on the similarity numbers.

 * "git format-patch" learned "--quiet" option to suppress the output of
   the names of generated files.

 * "git format-patch" quotes people's names when it has RFC822 special
   characters in it, e.g. "Junio C. Hamano" <jch@example.com>.  Earlier
   it was up to the user to do this when using its output.

 * "git format-patch" can take an empty --subject-prefix now.

 * "git grep" learned the "-P" option to take pcre regular expressions.

 * "git log" and friends learned a new "--notes" option to replace the
   "--show-notes" option.  Unlike "--show-notes", "--notes=<ref>" does
   not imply showing the default notes.

 * They also learned a log.abbrevCommit configuration variable to augment
   the --abbrev-commit command line option.

 * "git ls-remote" learned "--exit-code" option to consider it a
   different kind of error when no remote ref to be shown.

 * "git merge" learned "-" as a short-hand for "the previous branch", just
   like the way "git checkout -" works.

 * "git merge" uses "merge.ff" configuration variable to decide to always
   create a merge commit (i.e. --no-ff, aka merge.ff=no), refuse to create
   a merge commit (i.e. --ff-only, aka merge.ff=only). Setting merge.ff=yes
   (or not setting it at all) restores the default behaviour of allowing
   fast-forward to happen when possible.

 * p4-import (from contrib) learned a new option --preserve-user.

 * "git read-tree -m" learned "--dry-run" option that reports if a merge
   would fail without touching the index nor the working tree.

 * "git rebase" that does not specify on top of which branch to rebase
   the current branch now uses @{upstream} of the current branch.

 * "git rebase" finished either normally or with --abort did not
   update the reflog for HEAD to record the event to come back to
   where it started from.

 * "git remote add -t only-this-branch --mirror=fetch" is now allowed. Earlier
   a fetch-mode mirror meant mirror everything, but now it only means refs are
   not renamed.

 * "git rev-list --count" used with "--cherry-mark" counts the cherry-picked
   commits separately, producing more a useful output.

 * "git submodule update" learned "--force" option to get rid of local
   changes in submodules and replace them with the up-to-date version.

 * "git status" and friends ignore .gitmodules file while the file is
   still in a conflicted state during a merge, to avoid using information
   that is not final and possibly corrupt with conflict markers.

Also contains various documentation updates and minor miscellaneous
changes.


Fixes since v1.7.5
------------------

Unless otherwise noted, all the fixes in 1.7.5.X maintenance track are
included in this release.

 * "git config" used to choke with an insanely long line.
   (merge ef/maint-strbuf-init later)

 * "git diff --quiet" did not work well with --diff-filter.
   (merge jk/diff-not-so-quick later)

 * "git status -z" did not default to --porcelain output format.
   (merge bc/maint-status-z-to-use-porcelain later)