cvsimport: skip commits that are too recent (option and documentation)

This makes the earlier "wait for 10 minutes before importing" safety
overridable with "-a(ll)" flag, and adds necessary documentation.

Signed-off-by: Martin Langhoff <martin@catalyst.net.nz>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-cvsimport.txt

@@ -90,7 +90,8 @@ If you need to pass multiple options, separate them with a comma.
 	Print a short usage message and exit.
 
 -z <fuzz>::
-        Pass the timestamp fuzz factor to cvsps.
+	Pass the timestamp fuzz factor to cvsps, in seconds. If unset,
+	cvsps defaults to 300s.
 
 -s <subst>::
 	Substitute the character "/" in branch names with <subst>
@@ -99,6 +100,10 @@ If you need to pass multiple options, separate them with a comma.
 	CVS by default uses the unix username when writing its
 	commit logs. Using this option and an author-conv-file
 	in this format
+
+-a::
+	Import all commits, including recent ones. cvsimport by default
+	skips commits that have a timestamp less than 10 minutes ago.
 +
 ---------
 	exon=Andreas Ericsson <ae@op5.se>

git-cvsimport.perl

@@ -29,15 +29,15 @@
 $SIG{'PIPE'}="IGNORE";
 $ENV{'TZ'}="UTC";
 
-our ($opt_h,$opt_o,$opt_v,$opt_k,$opt_u,$opt_d,$opt_p,$opt_C,$opt_z,$opt_i,$opt_P, $opt_s,$opt_m,$opt_M,$opt_A,$opt_S,$opt_L);
+our ($opt_h,$opt_o,$opt_v,$opt_k,$opt_u,$opt_d,$opt_p,$opt_C,$opt_z,$opt_i,$opt_P, $opt_s,$opt_m,$opt_M,$opt_A,$opt_S,$opt_L, $opt_a);
 my (%conv_author_name, %conv_author_email);
 
 sub usage() {
 	print STDERR <<END;
 Usage: ${\basename $0}     # fetch/update GIT from CVS
        [-o branch-for-HEAD] [-h] [-v] [-d CVSROOT] [-A author-conv-file]
        [-p opts-for-cvsps] [-C GIT_repository] [-z fuzz] [-i] [-k] [-u]
-       [-s subst] [-m] [-M regex] [-S regex] [CVS_module]
+       [-s subst] [-a] [-m] [-M regex] [-S regex] [CVS_module]
 END
 	exit(1);
 }
@@ -105,6 +105,8 @@ ($)
 }
 $opt_o ||= "origin";
 $opt_s ||= "-";
+$opt_a ||= 0;
+
 my $git_tree = $opt_C;
 $git_tree ||= ".";
 
@@ -829,7 +831,7 @@ sub commit {
 			$state = 11;
 			next;
 		}
-		if ( $starttime - 300 - (defined $opt_z ? $opt_z : 300) <= $date) {
+		if (!$opt_a && $starttime - 300 - (defined $opt_z ? $opt_z : 300) <= $date) {
 			# skip if the commit is too recent
 			# that the cvsps default fuzz is 300s, we give ourselves another
 			# 300s just in case -- this also prevents skipping commits