hierarchical_select 5.x-3.0-rc3

Changes since DRUPAL-5--3-0-RC2:

• #292954 by Vuds: hs_book_hierarchical_select_valid_item()'s query fails when a module is installed that applies db_rewrite_sql() on it
• Follow-up patch for #284485: allow use of HS widget even if taxonomy isn't hierarchical, but now also in a Taxonomy exposed filter
• Prevent notices on the config export form.
• Added the concept of 'context type' and 'context', which allows for more accurate HS config management.
• Implemented #276731: Status report check: Hierarchical Select must have a higher weight than the Hierarchical Select implementations
• #294630: Clarify that a vocabulary's Multiple select setting is now managed by HS.
• Improved the manipulation of view settings through the HS config form.
• Fixed #294313, sponsored by mzenner: Force Single losing last selection
• Implemented #291626: change-hierarchical-select event
• #284719 by jrbeeman: Document how to theme views exposed filters to play nicely with HS
• Fixed #296254: Unable to set the parent of a term/container/forum
• Fixed #298260: Firefox 3.0.1 menu children must be double clicked
• #297104: hook_requirements() should check if the module has been installed in "modules"
• Fixed #298322: Regression: creation of new levels broken