function _deletePath(schema, name) {
  const pieces = name.split('.');
  const last = pieces.pop();

  let branch = schema.tree;

  for (const piece of pieces) {
    branch = branch[piece];
  }

  delete branch[last];
}
Removes the given `path` (or [`paths`]).

#### Example:

    const schema = new Schema({ name: String, age: Number });
    schema.remove('name');
    schema.path('name'); // Undefined
    schema.path('age'); // SchemaNumber { ... }

Or as a Array:

    schema.remove(['name', 'age']);
    schema.path('name'); // Undefined
    schema.path('age'); // Undefined

@param {String|Array} path The Path(s) to remove
@return {Schema} the Schema instance
@api public