Add config_int() method to the Git perl module

Integer variables can have optional 'k', 'm' or 'g' suffix.
config_int() method will return simple decimal number, taking
care of those suffixes.

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

perl/Git.pm

@@ -549,6 +549,37 @@ sub config_bool {
 	};
 }
 
+=item config_int ( VARIABLE )
+
+Retrieve the integer configuration C<VARIABLE>. The return value
+is simple decimal number.  An optional value suffix of 'k', 'm',
+or 'g' in the config file will cause the value to be multiplied
+by 1024, 1048576 (1024^2), or 1073741824 (1024^3) prior to output.
+It would return C<undef> if configuration variable is not defined,
+
+Must be called on a repository instance.
+
+This currently wraps command('config') so it is not so fast.
+
+=cut
+
+sub config_int {
+	my ($self, $var) = @_;
+	$self->repo_path()
+		or throw Error::Simple("not a repository");
+
+	try {
+		return $self->command_oneline('config', '--int', '--get', $var);
+	} catch Git::Error::Command with {
+		my $E = shift;
+		if ($E->value() == 1) {
+			# Key not found.
+			return undef;
+		} else {
+			throw $E;
+		}
+	};
+}
 
 =item ident ( TYPE | IDENTSTR )