use .send(Kaminari.config.page_method_name) instead of .page()

will_paginate and kaminari fight each other. the following makes them tolerate each other

```ruby
if defined?(WillPaginate)
  module WillPaginate
    module ActiveRecord
      module RelationMethods
        alias_method :per, :per_page
        alias_method :num_pages, :total_pages
      end
    end
  end
  ::ActiveRecord::Relation.send :include, Kaminari::ActiveRecordRelationMethods
  ::ActiveRecord::Relation.send :include, Kaminari::PageScopeMethods
end
```

but `build_searcher()` causes kaminaris `rel_next_prev_link_tags()` to fail

with this patch it is possible to use kaminaris `config.page_method_name = :kaminari_page` which allows them to play nice