new .executeAction() API for StoreMixin

This patch wraps `this.props.context.executeAction()` to `this.executeAction()` to stop expose context location in code of components. When the context location moved to other place or the context solution changes, this will make all components safe from these change.

Possible context solutions:
https://github.com/brianmcd/contextify
https://www.tildedave.com/2014/11/15/introduction-to-contexts-in-react-js.html