Merge branch 'jc/ident'

* jc/ident:
  ident.c: replace fprintf with fputs to suppress compiler warning
  user_ident_sufficiently_given(): refactor the logic to be usable from elsewhere
  ident.c: treat $EMAIL as giving user.email identity explicitly
  ident.c: check explicit identity for name and email separately
  ident.c: remove unused variables

diff --cc builtin-commit.c
Simple merge

diff --cc cache.h
Simple merge

diff --cc config.c
Simple merge