The first batch of topics after the 2.14 cycle

Notably, let's declare that we aim to make "git add ''" illegal in
the cycle after this one.

The topic to do so, ex/deprecate-empty-pathspec-as-match-all, has
been cooking in 'next' too long, and will stay there during this
cycle, but not after.

Signed-off-by: Junio C Hamano <gitster@pobox.com>