Name completion usability enhancements
Name completion usability enhancements

* Nickname select box now appears as soon as the trigger key (default `@`) is pressed
* Up/Down arrow keys in select box no longer allow you to scroll off the top or bottom
* Fixed off-by-one error that was causing autocomplete to ignore the last character typed

jansing/candy-plugins,csusantha/candy-plugins,kripton/candy-plugins,MOZGIII/candy-plugins,candy-chat/candy-plugins