mailmap: add mailmap structure to rev_info and pp

Pass a mailmap from rev_info to pretty_print_context to so that the
pretty printer can use rewritten name and email address when showing
commits.

Signed-off-by: Antoine Pelisse <apelisse@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

commit.h

@@ -89,6 +89,7 @@ struct pretty_print_context {
 	char *notes_message;
 	struct reflog_walk_info *reflog_info;
 	const char *output_encoding;
+	struct string_list *mailmap;
 };
 
 struct userformat_want {

log-tree.c

@@ -671,6 +671,7 @@ void show_log(struct rev_info *opt)
 	ctx.preserve_subject = opt->preserve_subject;
 	ctx.reflog_info = opt->reflog_info;
 	ctx.fmt = opt->commit_format;
+	ctx.mailmap = opt->mailmap;
 	pretty_print_commit(&ctx, commit, &msgbuf);
 
 	if (opt->add_signoff)

revision.h

@@ -143,6 +143,7 @@ struct rev_info {
 	const char	*subject_prefix;
 	int		no_inline;
 	int		show_log_size;
+	struct string_list *mailmap;
 
 	/* Filter by commit log message */
 	struct grep_opt	grep_filter;