Block Sorting & Deletion
Made corrections to Block sorting
  - Changed sorting to used sorted with appropriate key
  - Added JS to update location index of blocks if changes occur (deletion/reordering)
  - Added Up/Down buttons as alternate movement method
Updated Image upload form styling and behaviour
  - Changed dropzone upload success behaviour to switch to image preview and auto-fill image form
  - Changed dropzone sizing, alignment, and default message
Added/Updated css classes for all block types and fields