List git.git authors consenting to relicense their code

Since re-using code from git.git proper is the quick way
forward, we need to list those who have given their consent
to do just that. The relicense permission is only valid for
use with libgit2, and only for GPLv2 + gcc-exception (as
specified by 'COPYING'.

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

git.git-authors

+# This document lists the authors that have given voice to
+# their decision regarding relicensing the GPL'd code from
+# git.git to the GPL + gcc-exception license used by libgit2.
+#
+# Note that the permission is given for libgit2 use only. For
+# other uses, you must ask each of the contributors yourself.
+#
+# To show the owners of a file in git.git, one can run the
+# following command:
+#
+#  git blame -C -C -M -- file | \
+#    sed -e 's/[^(]*(\([^0-9]*\).*/\1/' -e 's/[\t ]*$//' | \
+#      sort | uniq -c | sort -nr
+#
+# If everyone on the list that produces are on the list in
+# the recently added file "git.git-authors", it *should* be
+# safe to include that code in libgit2, but make sure to
+# read the file to ensure the code doesn't originate from
+# somewhere else.
+#
+# The format of this list is
+# "ok/no/ask/???"<tab>"Author"<space>"<email>"
+#
+# "ok" means the author consents to relicensing all their
+#   contributed code (possibly with some exceptions)
+# "no" means the author does not consent
+# "ask" means that the contributor wants to give/withhold
+#   his/her consent on a patch-by-patch basis.
+# "???" means the person is a prominent contributor who has
+#   not yet made his/her standpoint clear.
+#
+# Please try to keep the list alphabetically ordered. It will
+# help in case we get all 600-ish git.git authors on it.
+#
+# (Paul Kocher is the author of the mozilla-sha1 implementation
+#  but has otherwise not contributed to git.)
+#
+ok	Andreas Ericsson <ae@op5.se>
+ok	Boyd Lynn Gerber <gerberb@zenez.com>
+ok	Brian Gernhardt <benji@silverinsanity.com>
+ok	Christian Couder <chriscool@tuxfamily.org>
+ok	Daniel Barkalow <barkalow@iabervon.org>
+ok	Jeff King <peff@peff.net>
+ok	Johannes Schindelin <Johannes.Schindelin@gmx.de>
+ok	Johannes Sixt <j6t@kdbg.org>
+ok	Junio C Hamano <gitster@pobox.com>
+ok	Linus Torvalds <torvalds@linux-foundation.org>
+ok	Lukas Sandström <lukass@etek.chalmers.se>
+ok	Nicolas Pitre <nico@cam.org>
+ok	Paolo Bonzini <bonzini@gnu.org>
+ok	Paul Kocher <paul@cryptography.com>
+ok	Peter Hagervall <hager@cs.umu.se>
+ok	Pierre Habouzit <madcoder@debian.org>
+ok	Pieter de Bie <pdebie@ai.rug.nl>
+ok	Shawn O. Pearce <spearce@spearce.org>