Ann T Ropea authored Dec 03, 2017 and Junio C Hamano committed Dec 04, 2017

Introduce a helper print_sha1_ellipsis() that pays attention to the
GIT_PRINT_SHA1_ELLIPSIS environment variable, and prepare the tests to
unconditionally set it for the test pieces that will be broken once the code
stops showing the extra dots by default.

The removal of these dots is merely a plan at this step and has not happened
yet but soon will.

Document GIT_PRINT_SHA1_ELLIPSIS.

Signed-off-by: Ann T Ropea <bedhanger@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>