Add path and path_natural sort orders

These correspond to title and title_natural, but compare the entire
path: a < a/b < a/z < ab < b.
(cherry picked from commit 903a5a314f)

t/cmp_path.t

@@ -0,0 +1,48 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+use Test::More tests => 25;
+
+BEGIN { use_ok("IkiWiki"); }
+
+%config=IkiWiki::defaultconfig();
+$config{srcdir}=$config{destdir}="/dev/null";
+IkiWiki::checkconfig();
+
+sub test {
+	my ($before, $after) = @_;
+
+	$IkiWiki::SortSpec::a = $before;
+	$IkiWiki::SortSpec::b = $after;
+	my $r = IkiWiki::SortSpec::cmp_path();
+
+	if ($before eq $after) {
+		is($r, 0);
+	}
+	else {
+		is($r, -1);
+	}
+
+	$IkiWiki::SortSpec::a = $after;
+	$IkiWiki::SortSpec::b = $before;
+	$r = IkiWiki::SortSpec::cmp_path();
+
+	if ($before eq $after) {
+		is($r, 0);
+	}
+	else {
+		is($r, 1);
+	}
+
+	is_deeply([IkiWiki::SortSpec::sort_pages(\&IkiWiki::SortSpec::cmp_path, $before, $after)],
+		[$before, $after]);
+	is_deeply([IkiWiki::SortSpec::sort_pages(\&IkiWiki::SortSpec::cmp_path, $after, $before)],
+		[$before, $after]);
+}
+
+test("a/b/c", "a/b/c");
+test("a/b", "a/c");
+test("a/z", "z/a");
+test("a", "a/b");
+test("a", "a/b");
+test("a/z", "ab");

t/pagespec_match_list.t

@@ -12,7 +12,7 @@ IkiWiki::checkconfig();
 {
 	package IkiWiki::SortSpec;
 
-	sub cmp_path { $a cmp $b }
+	sub cmp_raw_path { $a cmp $b }
 }
 
 %pagesources=(
@@ -53,7 +53,7 @@ is_deeply([pagespec_match_list("foo", "post/*", sort => "title", num => 50, reve
 is_deeply([pagespec_match_list("foo", "post/*", sort => "title",
                          filter => sub { $_[0] =~ /3/}) ],
 	["post/1", "post/2"]);
-is_deeply([pagespec_match_list("foo", "*", sort => "path", num => 2)],
+is_deeply([pagespec_match_list("foo", "*", sort => "raw_path", num => 2)],
 	["bar", "foo"]);
 is_deeply([pagespec_match_list("foo", "foo* or bar*",
 		sort => "-age title")], # oldest first, break ties by title