Improve UI elements for blocks editor

[nk-o]

Blocks

1. Accordion
   • [x] + Button to add accordion block
2. Accordion item
   • [x] - Button to remove block
   • [x] Collapsed option in toolbar and inspector
3. Alert
   • [x] Icon dropdown in block preview
4. Buttons
   • [x] Icon dropdown in block preview
   • [x] + Button to add button block
   • [ ] Gap option in Toolbar
5. Button
   • [x] - Button to remove block
   • [x] Icon dropdown in block preview
   • [ ] Size option in Toolbar
   • [ ] Icon Position option in icon picker dropdown
6. Number Box
   • [x] Number Position option in Toolbar
7. Divider
   • [x] Icon dropdown in block preview
   • [ ] Type option in Toolbar
8. Google Maps
   • [x] Add Marker option in Toolbar
   • [x] Style option in Toolbar
   • [x] Better Style selector with image preview (probably from Snazzy Maps API)
   • [x] Resize block height by dragging
9. Grid
   • [x] Hide options from Inspector if no layout selected
   • [x] Change predefined layouts to flex and css without any svg images
   • [ ] Gap option in Toolbar
10. Grid Column
    • [ ] Sticky option in Toolbar
11. Icon Box
    • [x] Icon dropdown in block preview
    • [x] Icon Position option in toolbar
12. Pricing Table
    • [x] + Button to add pricing block
    • [ ] Gap option in Toolbar
13. Pricing Table Item
    • [x] - Button to remove block
14. Progress
    • [x] Resize indicator when block selected, so user will know that they may change
    • [ ] Show Count option in Toolbar
    • [ ] Striped option in Toolbarheight and width by dragging
15. Tabs
    • [x] Align option in Toolbar
    • [x] + Button to add tab
    • [x] - Button to remove block
16. Testimonial
    • [x] Icon dropdown in block preview
    • [ ] Image option in Toolbar
17. Video
    • [x] Icon dropdown in block preview
    • [x] Aspect Ratio image selector instead of selector
    • [x] URL for YouTube/Vimeo option in Toolbar
    • [x] Aspect Ratio option in Toolbar
    • [ ] Type option in Toolbar
    • [ ] Click Action option in Toolbar
    • [ ] Poster Image option in Toolbar