Change Log: `yii2-sortable-input`

Version 1.2.1

Date: 29-Aug-2018

(bug #12): Correct sortable input plugin for the latest html5sortable release.
Add github contribution and PR/issue log templates.
Fix composer settings
Update copyright year to current.
Reorganize source code in src directory.

Version 1.2.0

Date: 29-Jan-2015

(enh #1): Plugin enhancement to update parent keys for connected sortables.

Version 1.1.0

Date: 10-Nov-2014

Set dependency on Krajee base components
Set release to stable

Version 1.0.0

Date: 01-Aug-2014

Initial release
PSR4 alias change