rename select method to set_heading_select to avoid conflicts

Pod::Usage subclasses Pod::Simple and implements its own select method.
That method tries to implement its own behavior but if a select method
exists in the parent it will call that instead. This is for
compatibility with inheriting from Pod::Parser instead.

Avoid that compatibility issue by renaming the select method. It has
only been available in a stable release for a few days and isn't yet
documented, so it's pretty unlikely anyone is using it yet.

Author: haarg

lib/Pod/Simple/BlackBox.pm

@@ -703,7 +703,7 @@ sub _filter_allows {
   return 0;
 }
 
-sub select {
+sub set_heading_select {
   my $self = shift;
   my (@selections) = @_;
 

t/filter-html.t

@@ -12,7 +12,7 @@ sub convert {
   $parser->html_header('');
   $parser->html_footer('');
   $parser->output_string(\$out);
-  $parser->select(@$select);
+  $parser->set_heading_select(@$select);
 
   $parser->parse_string_document($pod);
   return $out;

t/filter.t

@@ -9,7 +9,7 @@ sub convert {
   my $out = '';
   my $parser = Pod::Simple::JustPod->new;
   $parser->output_string(\$out);
-  $parser->select(@$select);
+  $parser->set_heading_select(@$select);
 
   $parser->parse_string_document($pod);
   return $out;