v1.2.1

1. Improved

• Grid can now set border and padding of childrens.
• Grid can control collection.
• Grid has default collection.
• Removed default styles of grid items.
• Added css for a bunch of content use-cases in grid-item.
• It's my birthday 🎂

2. Bugfix

• Empty p elements should now be hidden.
• Fixed some line break comming from embed shortcodes.