Merge pull request #749 from luckylooke/patch-3

Added data-gs-id to item attributes list

Author: radiolips

doc/README.md

@@ -103,6 +103,7 @@ gridstack.js API
 
 - `data-gs-x`, `data-gs-y` - element position
 - `data-gs-width`, `data-gs-height` - element size
+- `data-gs-id`- good for quick identification (for example in change event)
 - `data-gs-max-width`, `data-gs-min-width`, `data-gs-max-height`, `data-gs-min-height` - element constraints
 - `data-gs-no-resize` - disable element resizing
 - `data-gs-no-move` - disable element moving