Feature request: Allow type: array in cellSchema

[RyanWarner]

Thank you for this great library.

I'd like to put images or custom components in my cells.

When I use the suggested Sanity schema, I get a type error, "Type '"array"' is not assignable to type '"block"'."

cellSchema: {
  name: 'content',
  type: 'array',
  title: 'Content',
  of: [
    {
      type: 'block'
    },
    {
      type: 'image'
    }
  ]
}

[davydog187]

@RyanWarner thank you for reporting! I was aware of this issue, but was unable to fix due to #4

Now that there seems to be a solution in place, I can resolve this issue.

However, I want to make you aware of something: you cannot have an array as a child of a block, which is what Sanity is complaining about. Right now, this library only allows a single block definition, but I will extend it to support multiple block types, e.g.

cellSchema: [{
    name: "table-block",
    type: "block",
    marks: [ ... ],
    lists: [ ... ]  
  },
  {  type: "my-custom-block" },
  {  type: "my-image" },
  ...
]

Let me know if this suits your needs