New `chosen:close` and `chosen:no_results` events... plus bug fixes!

New events

• harvesthq#1663 Add chosen:close triggerable event to go with chosen:open
• harvesthq#1712 Empty search triggers chosen:no_results event

Loads of bug fixes and small improvements

• harvesthq#1430 Use document.createElement instead of html string
• harvesthq#1461 Single select results in sync
• harvesthq#1478 Trigger/Fire Results Showing Event After Winnow
• harvesthq#1603 Add support for paste events
• harvesthq#1702 Remove use of $.fn.is() in favor of more widely supported methods.
• harvesthq#1736 Set sprite source URLs to default, allowing them to be overridden from outside Chosen.
• harvesthq#1744 Remove linear-gradient from single select input background
• harvesthq#1745 Fix closing selects in pop out windows

Sweet, sweet documentation updates

• harvesthq#1429, harvesthq#1443, harvesthq#1457, harvesthq#1470, harvesthq#1501, harvesthq#1602, harvesthq#1741, harvesthq#1766