Reorder token with drag and drop

[David-Desmaisons]

This pull request introduces the ability to use drag and drop to reorder token (associated issue: #59 ).
To enable this behaviour, use the option {sortable: true}.
Two new events have been created 'tokenfield:sorttoken' and 'tokenfield:sortedtoken' both receiving the same option event argurment with the following attribute: attrs: attributes of the token been moved, oldPosition: old position in the list, newPosition: new position in the list.
It is possible cancel drag and drop in the 'tokenfield:sorttoken' event by doing return false or calling event.preventDefault().
The implementation uses jquery sortable plugin so you need to include jquery.ui to make it work.

[horacepan]

Are there plans to have this merged into master?

[firstthumb]

I am waiting for this feature.

[crowezie]

Ya this would be great to have

[manojLondhe]

+1 Maintainers will you please review and merge this one?

[manojLondhe]

@David-Desmaisons Try sending PR to these guys https://github.com/Open-Xchange-Frontend/bootstrap-tokenfield
They seem to have lots of work going on this plugin. What say @dotcore ?

[David-Desmaisons]

@manojLondhe thanks for the suggestion. I am quite busy right now with other projects but I may take some time in the future to submit the PR to https://github.com/Open-Xchange-Frontend/bootstrap-tokenfield

[crowezie]

@David-Desmaisons I was playing with this in a rails project and the sorting of tokens works great, but when I submit my tokenfield form they aren't saved in their new positions. Do I need to actually store the position to make it work?

[David-Desmaisons]

@crowezie I will have to check. It has been one year since I submit this PR! I may have some time this week-end to check the issue.