Fix pagination for default language when using the "Hide URL language information for default language" option of Polylang.
Issue #7: Add ending slash on link build with the "get_post_type_archive_link" function.
Simplification of the code for post type by using Wordpress functions directly.
UPGRADE NOTICE: If you used a version prior to 0.3.0, the plugin will probably crash as the structure of the param for the "pll_translated_post_type_rewrite_slugs" filter has changed.
- Fix issue #2;
- Use more native WordPress function;
- More stable.