by Dave Reid: Provide a better context upgrade path and a default sitemap with empty context on module install.

#762346 by Dave Reid: Fixed xmlsitemap_taxonomy_form_taxonomy_form_term_alter() from altering the term deletion form.

by Dave Reid: Moved the xmlsitemap_form_submit_flag_regenerate submit handlers to more specific locations.

#711510 by kiamlaluno: Removed vertical_tabs recommendation from xmlsitemap.info since it's already in Drupal 7 core.

by Dave Reid: Changed generation to work by basic contexts instead of hard-coded language and added temporary context fallback.

by Dave Reid: Changed xmlsitemap_add_form_link_options() to use entity, bundle, and ID parameters instead of a link array.