Merge pull request #1311 from koenpunt/replace-prop

Replace prop for jQuery legacy support
Added 'Add item link'
Updated use of Add options
Guard against adding already selected options
Ported 'Add Item' link to chosen.proto
Regenerate js files
Performance fix for deciding when to show the "Add this item" link
Ported performance fix to prototype
Regenerate js files for performance fix
Updated callback parameter to object with `value` and `text` property
Show add item link even for prefix matches
c57d1d6
hiding select.chzn-select was a bad idea, in general! reverting
923c3b2
Do no harm and return as soon as possible for unsupported browsers, name...
Prototype merge
Fixed adding options
Add <option /> with selected attribute

Add <option /> with selected attribute instead of selecting it
afterwards with JS
Updated the way for adding items using a custom callback
removed debug console.log
Updated examples
Fixes issues with adding options in prototype version
Added option for adding values by keyboard
persistent_create_option was not implemented in prototype version
removed console.log
Brought up to date with latest harvesthq/master