code: func (t Typed) StringsIf(key string) ([]string, bool) {
  	value, exists := t[key]
  	if exists == false {
  		return nil, false
  	}
  	if n, ok := value.([]string); ok {
  		return n, true
  	}
  	if a, ok := value.([]interface{}); ok {
  		l := len(a)
  		n := make([]string, l)
  		var ok bool
  		for i := 0; i < l; i++ {
  			if n[i], ok = a[i].(string); ok == false {
  				return n, false
  			}
  		}
  		return n, true
  	}
  	return nil, false
  }
docs: // Returns a string slice + true if valid
  // Returns nil + false otherwise
  // (returns nil+false if one of the values is not a valid string)