Act on a field being created.
This hook lets modules react to the creation of a field. It is called after the definition is saved, so it cannot be used to modify the field itself.
$field: The field just created.
Note: this list is generated by pattern matching, so it may include some functions that are not actually implementations of this hook.
function hook_field_create_field($field) {
// @todo Needs function body.
}