Merge branch 'jc/send-email-sensible-encoding'

"git send-email" used to accept a mistaken "y" (or "yes") as an
answer to "What encoding do you want to use [UTF-8]? " without
questioning.  Now it asks for confirmation when the answer looks
too short to be a valid encoding name.

* jc/send-email-sensible-encoding:
  send-email: ask confirmation if given encoding name is very short

diff --cc git-send-email.perl
Simple merge